Methods and apparatus for wireless transmit/receive unit (WTRU) power control

ABSTRACT

Methods and apparatus for wireless transmit/receive unit (WTRU) power control are described. A method includes receiving a time domain resource allocation (TDRA) list configuration including entries, each including a resource allocation that includes a slot offset value. L1 signaling is received indicating a minimum slot offset value. Downlink control information (DCI) is decoded on a physical downlink control channel in a slot. An index is obtained from the decoded DCI, identifying an entry in the TDRA list. A particular slot offset value identified by the index is retrieved from the TDRA list and compared with the minimum slot offset value. If the particular slot offset value is less than the minimum slot offset value, the entry is invalid. If the particular slot offset value is greater than or equal to the minimum slot offset value, a physical downlink shared channel is received.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is the U.S. National Stage, under 35 U.S.C. § 371, ofInternational Application No. PCT/US2019/047429 filed Aug. 21, 2019,which claims the benefit of U.S. Provisional Application No. 62/720,547,filed Aug. 21, 2018, U.S. Provisional Application No. 62/735,939, filedSep. 25, 2018, U.S. Provisional Application No. 62/752,797, filed Oct.30, 2018, U.S. Provisional Application No. 62/753,597, filed Oct. 31,2018, U.S. Provisional Application No. 62/840,935, filed Apr. 30, 2019,and U.S. Provisional Application No. 62/886,083, filed Aug. 13, 2019,the contents of which are incorporated herein by reference.

BACKGROUND

Next generation air interfaces, including further evolution of LTEAdvanced Pro and New Radio (NR), are expected to support a wide range ofuse cases. Such use cases may have varying service requirements, such aslow overhead low data rate power efficient services (mMTC),ultra-reliable low latency services (URLLC) and high data rate mobilebroadband services (eMBB)), for diverse WTRU capabilities, such as lowpower low bandwidth, very wide bandwidth (e.g., 80 Mhz), and highfrequency (e.g., >6 Ghz). Such use cases may have different spectrumusage models, such as licensed or unlicensed/shared, and may operateunder various mobility scenarios, such as stationary/fixed or high speedtrains using an architecture that is flexible enough to adapt to diversedeployment scenarios, such as standalone, non-standalone with assistancefrom a different air interface, centralized, virtualized, or distributedover ideal/non-ideal backhaul.

SUMMARY

Methods and apparatus for wireless transmit/receive unit (WTRU) powercontrol are described. A method includes receiving a time domainresource allocation (TDRA) list configuration including entries, eachincluding a resource allocation that includes a slot offset value. L1signaling is received indicating a minimum slot offset value. Downlinkcontrol information (DCI) is decoded on a physical downlink controlchannel in a slot. An index is obtained from the decoded DCI,identifying an entry in the TDRA list. A particular slot offset valueidentified by the index is retrieved from the TDRA list and comparedwith the minimum slot offset value. If the particular slot offset valueis less than the minimum slot offset value, the entry is invalid. If theparticular slot offset value is greater than or equal to the minimumslot offset value, a physical downlink shared channel is received.

BRIEF DESCRIPTION OF THE DRAWINGS

A more detailed understanding may be had from the following description,given by way of example in conjunction with the accompanying drawings,wherein like reference numerals in the figures indicate like elements,and wherein:

FIG. 1A is a system diagram illustrating an example communicationssystem in which one or more disclosed embodiments may be implemented;

FIG. 1B is a system diagram illustrating an example wirelesstransmit/receive unit (WTRU) that may be used within the communicationssystem illustrated in FIG. 1A according to an embodiment;

FIG. 1C is a system diagram illustrating an example radio access network(RAN) and an example core network (CN) that may be used within thecommunications system illustrated in FIG. 1A according to an embodiment;

FIG. 1D is a system diagram illustrating a further example RAN and afurther example CN that may be used within the communications systemillustrated in FIG. 1A according to an embodiment;

FIG. 2 is a diagram of an example of discontinuous reception (DRX);

FIG. 3 is a diagram of an example DRX cycle with wake up and go-to-sleepsignaling;

FIG. 4 is a diagram of example channel state information (CSI) resourceand CSI reporting configurations;

FIG. 5 is a flow diagram of an example method of WTRU power control;

FIG. 6 is a diagram of an example WTRU configured with multiple receivercomponents that may correspond to different power modes;

FIG. 7 is a system diagram showing an example usage of a low power modereceiver in different coverage scenarios;

FIG. 8 is a diagram of an example of switching between two radioperformance states;

FIG. 9 is a signal diagram of an example of multiple DRX configurationsbased on power mode;

FIG. 10 is a signal diagram of an example of power mode switchingbetween ON durations in different DRX cycles;

FIG. 11 is a signal diagram of an example of a wake up signal (WUS)determining a power mode of associated PDCCH monitoring occasions and aset of aggregation levels for the physical downlink control channel(PDCCH) monitoring;

FIG. 12 is a signal diagram of an example of aperiodic CSI reportingtriggering with associated power mode indication;

FIG. 13 is a signal diagram of an example of periodic CSI referencesignal (CSI-RS) and aperiodic CSI reporting;

FIG. 14 is a signal diagram of an example of periodic CSI-RS andperiodic CSI reporting;

FIG. 15 is a signal diagram of an example maximum rank restriction witha timer;

FIG. 16 is a graph showing an example of the number of receive radiofrequency (Rx RF) chains decrementing based on radio link monitoring(RLM) measurement;

FIG. 17 is a graph showing a number of Rx RF chains incrementing basedon RLM measurement; and

FIG. 18 is a signal diagram of an example of processing are-synchronization signal (RSS) in conjunction with a DRX ON durationtime interval.

DETAILED DESCRIPTION

FIG. 1A is a diagram illustrating an example communications system 100in which one or more disclosed embodiments may be implemented. Thecommunications system 100 may be a multiple access system that providescontent, such as voice, data, video, messaging, broadcast, etc., tomultiple wireless users. The communications system 100 may enablemultiple wireless users to access such content through the sharing ofsystem resources, including wireless bandwidth. For example, thecommunications systems 100 may employ one or more channel accessmethods, such as code division multiple access (CDMA), time divisionmultiple access (TDMA), frequency division multiple access (FDMA),orthogonal FDMA (OFDMA), single-carrier FDMA (SC-FDMA), zero-tailunique-word discrete Fourier transform Spread OFDM (ZT-UW-DFT-S-OFDM),unique word OFDM (UW-OFDM), resource block-filtered OFDM, filter bankmulticarrier (FBMC), and the like.

As shown in FIG. 1A, the communications system 100 may include wirelesstransmit/receive units (WTRUs) 102 a, 102 b, 102 c, 102 d, a radioaccess network (RAN) 104, a core network (CN) 106, a public switchedtelephone network (PSTN) 108, the Internet 110, and other networks 112,though it will be appreciated that the disclosed embodiments contemplateany number of WTRUs, base stations, networks, and/or network elements.Each of the WTRUs 102 a, 102 b, 102 c, 102 d may be any type of deviceconfigured to operate and/or communicate in a wireless environment. Byway of example, the WTRUs 102 a, 102 b, 102 c, 102 d, any of which maybe referred to as a station (STA), may be configured to transmit and/orreceive wireless signals and may include a user equipment (UE), a mobilestation, a fixed or mobile subscriber unit, a subscription-based unit, apager, a cellular telephone, a personal digital assistant (PDA), asmartphone, a laptop, a netbook, a personal computer, a wireless sensor,a hotspot or Mi-Fi device, an Internet of Things (IoT) device, a watchor other wearable, a head-mounted display (HMD), a vehicle, a drone, amedical device and applications (e.g., remote surgery), an industrialdevice and applications (e.g., a robot and/or other wireless devicesoperating in an industrial and/or an automated processing chaincontexts), a consumer electronics device, a device operating oncommercial and/or industrial wireless networks, and the like. Any of theWTRUs 102 a, 102 b, 102 c and 102 d may be interchangeably referred toas a UE.

The communications systems 100 may also include a base station 114 aand/or a base station 114 b. Each of the base stations 114 a, 114 b maybe any type of device configured to wirelessly interface with at leastone of the WTRUs 102 a, 102 b, 102 c, 102 d to facilitate access to oneor more communication networks, such as the CN 106, the Internet 110,and/or the other networks 112. By way of example, the base stations 114a, 114 b may be a base transceiver station (BTS), a NodeB, an eNode B(eNB), a Home Node B, a Home eNode B, a next generation NodeB, such as agNode B (gNB), a new radio (NR) NodeB, a site controller, an accesspoint (AP), a wireless router, and the like. While the base stations 114a, 114 b are each depicted as a single element, it will be appreciatedthat the base stations 114 a, 114 b may include any number ofinterconnected base stations and/or network elements.

The base station 114 a may be part of the RAN 104, which may alsoinclude other base stations and/or network elements (not shown), such asa base station controller (BSC), a radio network controller (RNC), relaynodes, and the like. The base station 114 a and/or the base station 114b may be configured to transmit and/or receive wireless signals on oneor more carrier frequencies, which may be referred to as a cell (notshown). These frequencies may be in licensed spectrum, unlicensedspectrum, or a combination of licensed and unlicensed spectrum. A cellmay provide coverage for a wireless service to a specific geographicalarea that may be relatively fixed or that may change over time. The cellmay further be divided into cell sectors. For example, the cellassociated with the base station 114 a may be divided into threesectors. Thus, in one embodiment, the base station 114 a may includethree transceivers, i.e., one for each sector of the cell. In anembodiment, the base station 114 a may employ multiple-input multipleoutput (MIMO) technology and may utilize multiple transceivers for eachsector of the cell. For example, beamforming may be used to transmitand/or receive signals in desired spatial directions.

The base stations 114 a, 114 b may communicate with one or more of theWTRUs 102 a, 102 b, 102 c, 102 d over an air interface 116, which may beany suitable wireless communication link (e.g., radio frequency (RF),microwave, centimeter wave, micrometer wave, infrared (IR), ultraviolet(UV), visible light, etc.). The air interface 116 may be establishedusing any suitable radio access technology (RAT).

More specifically, as noted above, the communications system 100 may bea multiple access system and may employ one or more channel accessschemes, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, and the like. Forexample, the base station 114 a in the RAN 104 and the WTRUs 102 a, 102b, 102 c may implement a radio technology such as Universal MobileTelecommunications System (UMTS) Terrestrial Radio Access (UTRA), whichmay establish the air interface 116 using wideband CDMA (WCDMA). WCDMAmay include communication protocols such as High-Speed Packet Access(HSPA) and/or Evolved HSPA (HSPA+). HSPA may include High-Speed Downlink(DL) Packet Access (HSDPA) and/or High-Speed Uplink (UL) Packet Access(HSUPA).

In an embodiment, the base station 114 a and the WTRUs 102 a, 102 b, 102c may implement a radio technology such as Evolved UMTS TerrestrialRadio Access (E-UTRA), which may establish the air interface 116 usingLong Term Evolution (LTE) and/or LTE-Advanced (LTE-A) and/orLTE-Advanced Pro (LTE-A Pro).

In an embodiment, the base station 114 a and the WTRUs 102 a, 102 b, 102c may implement a radio technology such as NR Radio Access, which mayestablish the air interface 116 using NR.

In an embodiment, the base station 114 a and the WTRUs 102 a, 102 b, 102c may implement multiple radio access technologies. For example, thebase station 114 a and the WTRUs 102 a, 102 b, 102 c may implement LTEradio access and NR radio access together, for instance using dualconnectivity (DC) principles. Thus, the air interface utilized by WTRUs102 a, 102 b, 102 c may be characterized by multiple types of radioaccess technologies and/or transmissions sent to/from multiple types ofbase stations (e.g., an eNB and a gNB).

In other embodiments, the base station 114 a and the WTRUs 102 a, 102 b,102 c may implement radio technologies such as IEEE 802.11 (i.e.,Wireless Fidelity (WiFi), IEEE 802.16 (i.e., Worldwide Interoperabilityfor Microwave Access (WiMAX)), CDMA2000, CDMA2000 1×, CDMA2000 EV-DO,Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), InterimStandard 856 (IS-856), Global System for Mobile communications (GSM),Enhanced Data rates for GSM Evolution (EDGE), GSM EDGE (GERAN), and thelike.

The base station 114 b in FIG. 1A may be a wireless router, Home Node B,Home eNode B, or access point, for example, and may utilize any suitableRAT for facilitating wireless connectivity in a localized area, such asa place of business, a home, a vehicle, a campus, an industrialfacility, an air corridor (e.g., for use by drones), a roadway, and thelike. In one embodiment, the base station 114 b and the WTRUs 102 c, 102d may implement a radio technology such as IEEE 802.11 to establish awireless local area network (WLAN). In an embodiment, the base station114 b and the WTRUs 102 c, 102 d may implement a radio technology suchas IEEE 802.15 to establish a wireless personal area network (WPAN). Inyet another embodiment, the base station 114 b and the WTRUs 102 c, 102d may utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE,LTE-A, LTE-A Pro, NR etc.) to establish a picocell or femtocell. Asshown in FIG. 1A, the base station 114 b may have a direct connection tothe Internet 110. Thus, the base station 114 b may not be required toaccess the Internet 110 via the CN 106.

The RAN 104 may be in communication with the CN 106, which may be anytype of network configured to provide voice, data, applications, and/orvoice over internet protocol (VoIP) services to one or more of the WTRUs102 a, 102 b, 102 c, 102 d. The data may have varying quality of service(QoS) requirements, such as differing throughput requirements, latencyrequirements, error tolerance requirements, reliability requirements,data throughput requirements, mobility requirements, and the like. TheCN 106 may provide call control, billing services, mobile location-basedservices, pre-paid calling, Internet connectivity, video distribution,etc., and/or perform high-level security functions, such as userauthentication. Although not shown in FIG. 1A, it will be appreciatedthat the RAN 104 and/or the CN 106 may be in direct or indirectcommunication with other RANs that employ the same RAT as the RAN 104 ora different RAT. For example, in addition to being connected to the RAN104, which may be utilizing a NR radio technology, the CN 106 may alsobe in communication with another RAN (not shown) employing a GSM, UMTS,CDMA 2000, WiMAX, E-UTRA, or WiFi radio technology.

The CN 106 may also serve as a gateway for the WTRUs 102 a, 102 b, 102c, 102 d to access the PSTN 108, the Internet 110, and/or the othernetworks 112. The PSTN 108 may include circuit-switched telephonenetworks that provide plain old telephone service (POTS). The Internet110 may include a global system of interconnected computer networks anddevices that use common communication protocols, such as thetransmission control protocol (TCP), user datagram protocol (UDP) and/orthe internet protocol (IP) in the TCP/IP internet protocol suite. Thenetworks 112 may include wired and/or wireless communications networksowned and/or operated by other service providers. For example, thenetworks 112 may include another CN connected to one or more RANs, whichmay employ the same RAT as the RAN 104 or a different RAT.

Some or all of the WTRUs 102 a, 102 b, 102 c, 102 d in thecommunications system 100 may include multi-mode capabilities (e.g., theWTRUs 102 a, 102 b, 102 c, 102 d may include multiple transceivers forcommunicating with different wireless networks over different wirelesslinks). For example, the WTRU 102 c shown in FIG. 1A may be configuredto communicate with the base station 114 a, which may employ acellular-based radio technology, and with the base station 114 b, whichmay employ an IEEE 802 radio technology.

FIG. 1B is a system diagram illustrating an example WTRU 102. As shownin FIG. 1B, the WTRU 102 may include a processor 118, a transceiver 120,a transmit/receive element 122, a speaker/microphone 124, a keypad 126,a display/touchpad 128, non-removable memory 130, removable memory 132,a power source 134, a global positioning system (GPS) chipset 136,and/or other peripherals 138, among others. It will be appreciated thatthe WTRU 102 may include any sub-combination of the foregoing elementswhile remaining consistent with an embodiment.

The processor 118 may be a general purpose processor, a special purposeprocessor, a conventional processor, a digital signal processor (DSP), aplurality of microprocessors, one or more microprocessors in associationwith a DSP core, a controller, a microcontroller, Application SpecificIntegrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs), anyother type of integrated circuit (IC), a state machine, and the like.The processor 118 may perform signal coding, data processing, powercontrol, input/output processing, and/or any other functionality thatenables the WTRU 102 to operate in a wireless environment. The processor118 may be coupled to the transceiver 120, which may be coupled to thetransmit/receive element 122. While FIG. 1B depicts the processor 118and the transceiver 120 as separate components, it will be appreciatedthat the processor 118 and the transceiver 120 may be integratedtogether in an electronic package or chip.

The transmit/receive element 122 may be configured to transmit signalsto, or receive signals from, a base station (e.g., the base station 114a) over the air interface 116. For example, in one embodiment, thetransmit/receive element 122 may be an antenna configured to transmitand/or receive RF signals. In an embodiment, the transmit/receiveelement 122 may be an emitter/detector configured to transmit and/orreceive IR, UV, or visible light signals, for example. In yet anotherembodiment, the transmit/receive element 122 may be configured totransmit and/or receive both RF and light signals. It will beappreciated that the transmit/receive element 122 may be configured totransmit and/or receive any combination of wireless signals.

Although the transmit/receive element 122 is depicted in FIG. 1B as asingle element, the WTRU 102 may include any number of transmit/receiveelements 122. More specifically, the WTRU 102 may employ MIMOtechnology. Thus, in one embodiment, the WTRU 102 may include two ormore transmit/receive elements 122 (e.g., multiple antennas) fortransmitting and receiving wireless signals over the air interface 116.

The transceiver 120 may be configured to modulate the signals that areto be transmitted by the transmit/receive element 122 and to demodulatethe signals that are received by the transmit/receive element 122. Asnoted above, the WTRU 102 may have multi-mode capabilities. Thus, thetransceiver 120 may include multiple transceivers for enabling the WTRU102 to communicate via multiple RATs, such as NR and IEEE 802.11, forexample.

The processor 118 of the WTRU 102 may be coupled to, and may receiveuser input data from, the speaker/microphone 124, the keypad 126, and/orthe display/touchpad 128 (e.g., a liquid crystal display (LCD) displayunit or organic light-emitting diode (OLED) display unit). The processor118 may also output user data to the speaker/microphone 124, the keypad126, and/or the display/touchpad 128. In addition, the processor 118 mayaccess information from, and store data in, any type of suitable memory,such as the non-removable memory 130 and/or the removable memory 132.The non-removable memory 130 may include random-access memory (RAM),read-only memory (ROM), a hard disk, or any other type of memory storagedevice. The removable memory 132 may include a subscriber identitymodule (SIM) card, a memory stick, a secure digital (SD) memory card,and the like. In other embodiments, the processor 118 may accessinformation from, and store data in, memory that is not physicallylocated on the WTRU 102, such as on a server or a home computer (notshown).

The processor 118 may receive power from the power source 134, and maybe configured to distribute and/or control the power to the othercomponents in the WTRU 102. The power source 134 may be any suitabledevice for powering the WTRU 102. For example, the power source 134 mayinclude one or more dry cell batteries (e.g., nickel-cadmium (NiCd),nickel-zinc (NiZn), nickel metal hydride (NiMH), lithium-ion (Li-ion),etc.), solar cells, fuel cells, and the like.

The processor 118 may also be coupled to the GPS chipset 136, which maybe configured to provide location information (e.g., longitude andlatitude) regarding the current location of the WTRU 102. In additionto, or in lieu of, the information from the GPS chipset 136, the WTRU102 may receive location information over the air interface 116 from abase station (e.g., base stations 114 a, 114 b) and/or determine itslocation based on the timing of the signals being received from two ormore nearby base stations. It will be appreciated that the WTRU 102 mayacquire location information by way of any suitablelocation-determination method while remaining consistent with anembodiment.

The processor 118 may further be coupled to other peripherals 138, whichmay include one or more software and/or hardware modules that provideadditional features, functionality and/or wired or wirelessconnectivity. For example, the peripherals 138 may include anaccelerometer, an e-compass, a satellite transceiver, a digital camera(for photographs and/or video), a universal serial bus (USB) port, avibration device, a television transceiver, a hands free headset, aBluetooth® module, a frequency modulated (FM) radio unit, a digitalmusic player, a media player, a video game player module, an Internetbrowser, a Virtual Reality and/or Augmented Reality (VR/AR) device, anactivity tracker, and the like. The peripherals 138 may include one ormore sensors. The sensors may be one or more of a gyroscope, anaccelerometer, a hall effect sensor, a magnetometer, an orientationsensor, a proximity sensor, a temperature sensor, a time sensor; ageolocation sensor, an altimeter, a light sensor, a touch sensor, amagnetometer, a barometer, a gesture sensor, a biometric sensor, ahumidity sensor and the like.

The WTRU 102 may include a full duplex radio for which transmission andreception of some or all of the signals (e.g., associated withparticular subframes for both the UL (e.g., for transmission) and DL(e.g., for reception) may be concurrent and/or simultaneous. The fullduplex radio may include an interference management unit to reduce andor substantially eliminate self-interference via either hardware (e.g.,a choke) or signal processing via a processor (e.g., a separateprocessor (not shown) or via processor 118). In an embodiment, the WTRU102 may include a half-duplex radio for which transmission and receptionof some or all of the signals (e.g., associated with particularsubframes for either the UL (e.g., for transmission) or the DL (e.g.,for reception)).

FIG. 10 is a system diagram illustrating the RAN 104 and the CN 106according to an embodiment. As noted above, the RAN 104 may employ anE-UTRA radio technology to communicate with the WTRUs 102 a, 102 b, 102c over the air interface 116. The RAN 104 may also be in communicationwith the CN 106.

The RAN 104 may include eNode-Bs 160 a, 160 b, 160 c, though it will beappreciated that the RAN 104 may include any number of eNode-Bs whileremaining consistent with an embodiment. The eNode-Bs 160 a, 160 b, 160c may each include one or more transceivers for communicating with theWTRUs 102 a, 102 b, 102 c over the air interface 116. In one embodiment,the eNode-Bs 160 a, 160 b, 160 c may implement MIMO technology. Thus,the eNode-B 160 a, for example, may use multiple antennas to transmitwireless signals to, and/or receive wireless signals from, the WTRU 102a.

Each of the eNode-Bs 160 a, 160 b, 160 c may be associated with aparticular cell (not shown) and may be configured to handle radioresource management decisions, handover decisions, scheduling of usersin the UL and/or DL, and the like. As shown in FIG. 10 , the eNode-Bs160 a, 160 b, 160 c may communicate with one another over an X2interface.

The CN 106 shown in FIG. 10 may include a mobility management entity(MME) 162, a serving gateway (SGW) 164, and a packet data network (PDN)gateway (PGW) 166. While the foregoing elements are depicted as part ofthe CN 106, it will be appreciated that any of these elements may beowned and/or operated by an entity other than the CN operator.

The MME 162 may be connected to each of the eNode-Bs 162 a, 162 b, 162 cin the RAN 104 via an S1 interface and may serve as a control node. Forexample, the MME 162 may be responsible for authenticating users of theWTRUs 102 a, 102 b, 102 c, bearer activation/deactivation, selecting aparticular serving gateway during an initial attach of the WTRUs 102 a,102 b, 102 c, and the like. The MME 162 may provide a control planefunction for switching between the RAN 104 and other RANs (not shown)that employ other radio technologies, such as GSM and/or WCDMA.

The SGW 164 may be connected to each of the eNode Bs 160 a, 160 b, 160 cin the RAN 104 via the S1 interface. The SGW 164 may generally route andforward user data packets to/from the WTRUs 102 a, 102 b, 102 c. The SGW164 may perform other functions, such as anchoring user planes duringinter-eNode B handovers, triggering paging when DL data is available forthe WTRUs 102 a, 102 b, 102 c, managing and storing contexts of theWTRUs 102 a, 102 b, 102 c, and the like.

The SGW 164 may be connected to the PGW 166, which may provide the WTRUs102 a, 102 b, 102 c with access to packet-switched networks, such as theInternet 110, to facilitate communications between the WTRUs 102 a, 102b, 102 c and IP-enabled devices.

The CN 106 may facilitate communications with other networks. Forexample, the CN 106 may provide the WTRUs 102 a, 102 b, 102 c withaccess to circuit-switched networks, such as the PSTN 108, to facilitatecommunications between the WTRUs 102 a, 102 b, 102 c and traditionalland-line communications devices. For example, the CN 106 may include,or may communicate with, an IP gateway (e.g., an IP multimedia subsystem(IMS) server) that serves as an interface between the CN 106 and thePSTN 108. In addition, the CN 106 may provide the WTRUs 102 a, 102 b,102 c with access to the other networks 112, which may include otherwired and/or wireless networks that are owned and/or operated by otherservice providers.

Although the WTRU is described in FIGS. 1A-1D as a wireless terminal, itis contemplated that in certain representative embodiments that such aterminal may use (e.g., temporarily or permanently) wired communicationinterfaces with the communication network.

In representative embodiments, the other network 112 may be a WLAN.

A WLAN in Infrastructure Basic Service Set (BSS) mode may have an AccessPoint (AP) for the BSS and one or more stations (STAs) associated withthe AP. The AP may have access or an interface to a Distribution System(DS) or another type of wired/wireless network that carries traffic into and/or out of the BSS. Traffic to STAs that originates from outsidethe BSS may arrive through the AP and may be delivered to the STAs.Traffic originating from STAs to destinations outside the BSS may besent to the AP to be delivered to respective destinations. Trafficbetween STAs within the BSS may be sent through the AP, for example,where the source STA may send traffic to the AP and the AP may deliverthe traffic to the destination STA. The traffic between STAs within aBSS may be considered and/or referred to as peer-to-peer traffic. Thepeer-to-peer traffic may be sent between (e.g., directly between) thesource and destination STAs with a direct link setup (DLS). In certainrepresentative embodiments, the DLS may use an 802.11e DLS or an 802.11ztunneled DLS (TDLS). A WLAN using an Independent BSS (IBSS) mode may nothave an AP, and the STAs (e.g., all of the STAs) within or using theIBSS may communicate directly with each other. The IBSS mode ofcommunication may sometimes be referred to herein as an “ad-hoc” mode ofcommunication.

When using the 802.11ac infrastructure mode of operation or a similarmode of operations, the AP may transmit a beacon on a fixed channel,such as a primary channel. The primary channel may be a fixed width(e.g., 20 MHz wide bandwidth) or a dynamically set width. The primarychannel may be the operating channel of the BSS and may be used by theSTAs to establish a connection with the AP. In certain representativeembodiments, Carrier Sense Multiple Access with Collision Avoidance(CSMA/CA) may be implemented, for example in 802.11 systems. ForCSMA/CA, the STAs (e.g., every STA), including the AP, may sense theprimary channel. If the primary channel is sensed/detected and/ordetermined to be busy by a particular STA, the particular STA may backoff. One STA (e.g., only one station) may transmit at any given time ina given BSS.

High Throughput (HT) STAs may use a 40 MHz wide channel forcommunication, for example, via a combination of the primary 20 MHzchannel with an adjacent or nonadjacent 20 MHz channel to form a 40 MHzwide channel.

Very High Throughput (VHT) STAs may support 20 MHz, 40 MHz, 80 MHz,and/or 160 MHz wide channels. The 40 MHz, and/or 80 MHz, channels may beformed by combining contiguous 20 MHz channels. A 160 MHz channel may beformed by combining 8 contiguous 20 MHz channels, or by combining twonon-contiguous 80 MHz channels, which may be referred to as an 80+80configuration. For the 80+80 configuration, the data, after channelencoding, may be passed through a segment parser that may divide thedata into two streams. Inverse Fast Fourier Transform (IFFT) processing,and time domain processing, may be done on each stream separately. Thestreams may be mapped on to the two 80 MHz channels, and the data may betransmitted by a transmitting STA. At the receiver of the receiving STA,the above described operation for the 80+80 configuration may bereversed, and the combined data may be sent to the Medium Access Control(MAC).

Sub 1 GHz modes of operation are supported by 802.11af and 802.11ah. Thechannel operating bandwidths, and carriers, are reduced in 802.11af and802.11ah relative to those used in 802.11n, and 802.11ac. 802.11afsupports 5 MHz, 10 MHz, and 20 MHz bandwidths in the TV White Space(TVWS) spectrum, and 802.11ah supports 1 MHz, 2 MHz, 4 MHz, 8 MHz, and16 MHz bandwidths using non-TVWS spectrum. According to a representativeembodiment, 802.11ah may support Meter Type Control/Machine-TypeCommunications (MTC), such as MTC devices in a macro coverage area. MTCdevices may have certain capabilities, for example, limited capabilitiesincluding support for (e.g., only support for) certain and/or limitedbandwidths. The MTC devices may include a battery with a battery lifeabove a threshold (e.g., to maintain a very long battery life).

WLAN systems, which may support multiple channels, and channelbandwidths, such as 802.11n, 802.11ac, 802.11af, and 802.11ah, include achannel which may be designated as the primary channel. The primarychannel may have a bandwidth equal to the largest common operatingbandwidth supported by all STAs in the BSS. The bandwidth of the primarychannel may be set and/or limited by a STA, from among all STAs inoperating in a BSS, which supports the smallest bandwidth operatingmode. In the example of 802.11ah, the primary channel may be 1 MHz widefor STAs (e.g., MTC type devices) that support (e.g., only support) a 1MHz mode, even if the AP, and other STAs in the BSS support 2 MHz, 4MHz, 8 MHz, 16 MHz, and/or other channel bandwidth operating modes.Carrier sensing and/or Network Allocation Vector (NAV) settings maydepend on the status of the primary channel. If the primary channel isbusy, for example, due to a STA (which supports only a 1 MHz operatingmode) transmitting to the AP, all available frequency bands may beconsidered busy even though a majority of the available frequency bandsremains idle.

In the United States, the available frequency bands, which may be usedby 802.11ah, are from 902 MHz to 928 MHz. In Korea, the availablefrequency bands are from 917.5 MHz to 923.5 MHz. In Japan, the availablefrequency bands are from 916.5 MHz to 927.5 MHz. The total bandwidthavailable for 802.11ah is 6 MHz to 26 MHz depending on the country code.

FIG. 1D is a system diagram illustrating the RAN 104 and the CN 106according to an embodiment. As noted above, the RAN 104 may employ an NRradio technology to communicate with the WTRUs 102 a, 102 b, 102 c overthe air interface 116. The RAN 104 may also be in communication with theCN 106.

The RAN 104 may include gNBs 180 a, 180 b, 180 c, though it will beappreciated that the RAN 104 may include any number of gNBs whileremaining consistent with an embodiment. The gNBs 180 a, 180 b, 180 cmay each include one or more transceivers for communicating with theWTRUs 102 a, 102 b, 102 c over the air interface 116. In one embodiment,the gNBs 180 a, 180 b, 180 c may implement MIMO technology. For example,gNBs 180 a, 108 b may utilize beamforming to transmit signals to and/orreceive signals from the gNBs 180 a, 180 b, 180 c. Thus, the gNB 180 a,for example, may use multiple antennas to transmit wireless signals to,and/or receive wireless signals from, the WTRU 102 a. In an embodiment,the gNBs 180 a, 180 b, 180 c may implement carrier aggregationtechnology. For example, the gNB 180 a may transmit multiple componentcarriers to the WTRU 102 a (not shown). A subset of these componentcarriers may be on unlicensed spectrum while the remaining componentcarriers may be on licensed spectrum. In an embodiment, the gNBs 180 a,180 b, 180 c may implement Coordinated Multi-Point (CoMP) technology.For example, WTRU 102 a may receive coordinated transmissions from gNB180 a and gNB 180 b (and/or gNB 180 c).

The WTRUs 102 a, 102 b, 102 c may communicate with gNBs 180 a, 180 b,180 c using transmissions associated with a scalable numerology. Forexample, the OFDM symbol spacing and/or OFDM subcarrier spacing may varyfor different transmissions, different cells, and/or different portionsof the wireless transmission spectrum. The WTRUs 102 a, 102 b, 102 c maycommunicate with gNBs 180 a, 180 b, 180 c using subframe or transmissiontime intervals (TTIs) of various or scalable lengths (e.g., containing avarying number of OFDM symbols and/or lasting varying lengths ofabsolute time).

The gNBs 180 a, 180 b, 180 c may be configured to communicate with theWTRUs 102 a, 102 b, 102 c in a standalone configuration and/or anon-standalone configuration. In the standalone configuration, WTRUs 102a, 102 b, 102 c may communicate with gNBs 180 a, 180 b, 180 c withoutalso accessing other RANs (e.g., such as eNode-Bs 160 a, 160 b, 160 c).In the standalone configuration, WTRUs 102 a, 102 b, 102 c may utilizeone or more of gNBs 180 a, 180 b, 180 c as a mobility anchor point. Inthe standalone configuration, WTRUs 102 a, 102 b, 102 c may communicatewith gNBs 180 a, 180 b, 180 c using signals in an unlicensed band. In anon-standalone configuration WTRUs 102 a, 102 b, 102 c may communicatewith/connect to gNBs 180 a, 180 b, 180 c while also communicatingwith/connecting to another RAN such as eNode-Bs 160 a, 160 b, 160 c. Forexample, WTRUs 102 a, 102 b, 102 c may implement DC principles tocommunicate with one or more gNBs 180 a, 180 b, 180 c and one or moreeNode-Bs 160 a, 160 b, 160 c substantially simultaneously. In thenon-standalone configuration, eNode-Bs 160 a, 160 b, 160 c may serve asa mobility anchor for WTRUs 102 a, 102 b, 102 c and gNBs 180 a, 180 b,180 c may provide additional coverage and/or throughput for servicingWTRUs 102 a, 102 b, 102 c.

Each of the gNBs 180 a, 180 b, 180 c may be associated with a particularcell (not shown) and may be configured to handle radio resourcemanagement decisions, handover decisions, scheduling of users in the ULand/or DL, support of network slicing, DC, interworking between NR andE-UTRA, routing of user plane data towards User Plane Function (UPF) 184a, 184 b, routing of control plane information towards Access andMobility Management Function (AMF) 182 a, 182 b and the like. As shownin FIG. 1D, the gNBs 180 a, 180 b, 180 c may communicate with oneanother over an Xn interface.

The CN 106 shown in FIG. 1D may include at least one AMF 182 a, 182 b,at least one UPF 184 a,184 b, at least one Session Management Function(SMF) 183 a, 183 b, and possibly a Data Network (DN) 185 a, 185 b. Whilethe foregoing elements are depicted as part of the CN 106, it will beappreciated that any of these elements may be owned and/or operated byan entity other than the CN operator.

The AMF 182 a, 182 b may be connected to one or more of the gNBs 180 a,180 b, 180 c in the RAN 104 via an N2 interface and may serve as acontrol node. For example, the AMF 182 a, 182 b may be responsible forauthenticating users of the WTRUs 102 a, 102 b, 102 c, support fornetwork slicing (e.g., handling of different protocol data unit (PDU)sessions with different requirements), selecting a particular SMF 183 a,183 b, management of the registration area, termination of non-accessstratum (NAS) signaling, mobility management, and the like. Networkslicing may be used by the AMF 182 a, 182 b in order to customize CNsupport for WTRUs 102 a, 102 b, 102 c based on the types of servicesbeing utilized WTRUs 102 a, 102 b, 102 c. For example, different networkslices may be established for different use cases such as servicesrelying on ultra-reliable low latency (URLLC) access, services relyingon enhanced massive mobile broadband (eMBB) access, services for MTCaccess, and the like. The AMF 182 a, 182 b may provide a control planefunction for switching between the RAN 104 and other RANs (not shown)that employ other radio technologies, such as LTE, LTE-A, LTE-A Pro,and/or non-3GPP access technologies such as WiFi.

The SMF 183 a, 183 b may be connected to an AMF 182 a, 182 b in the CN106 via an N11 interface. The SMF 183 a, 183 b may also be connected toa UPF 184 a, 184 b in the CN 106 via an N4 interface. The SMF 183 a, 183b may select and control the UPF 184 a, 184 b and configure the routingof traffic through the UPF 184 a, 184 b. The SMF 183 a, 183 b mayperform other functions, such as managing and allocating UE IP address,managing PDU sessions, controlling policy enforcement and QoS, providingDL data notifications, and the like. A PDU session type may be IP-based,non-IP based, Ethernet-based, and the like.

The UPF 184 a, 184 b may be connected to one or more of the gNBs 180 a,180 b, 180 c in the RAN 104 via an N3 interface, which may provide theWTRUs 102 a, 102 b, 102 c with access to packet-switched networks, suchas the Internet 110, to facilitate communications between the WTRUs 102a, 102 b, 102 c and IP-enabled devices. The UPF 184, 184 b may performother functions, such as routing and forwarding packets, enforcing userplane policies, supporting multi-homed PDU sessions, handling user planeQoS, buffering DL packets, providing mobility anchoring, and the like.

The CN 106 may facilitate communications with other networks. Forexample, the CN 106 may include, or may communicate with, an IP gateway(e.g., an IP multimedia subsystem (IMS) server) that serves as aninterface between the CN 106 and the PSTN 108. In addition, the CN 106may provide the WTRUs 102 a, 102 b, 102 c with access to the othernetworks 112, which may include other wired and/or wireless networksthat are owned and/or operated by other service providers. In oneembodiment, the WTRUs 102 a, 102 b, 102 c may be connected to a local DN185 a, 185 b through the UPF 184 a, 184 b via the N3 interface to theUPF 184 a, 184 b and an N6 interface between the UPF 184 a, 184 b andthe DN 185 a, 185 b.

In view of FIGS. 1A-1D, and the corresponding description of FIGS.1A-1D, one or more, or all, of the functions described herein withregard to one or more of: WTRU 102 a-d, Base Station 114 a-b, eNode-B160 a-c, MME 162, SGW 164, PGW 166, gNB 180 a-c, AMF 182 a-b, UPF 184a-b, SMF 183 a-b, DN 185 a-b, and/or any other device(s) describedherein, may be performed by one or more emulation devices (not shown).The emulation devices may be one or more devices configured to emulateone or more, or all, of the functions described herein. For example, theemulation devices may be used to test other devices and/or to simulatenetwork and/or WTRU functions.

The emulation devices may be designed to implement one or more tests ofother devices in a lab environment and/or in an operator networkenvironment. For example, the one or more emulation devices may performthe one or more, or all, functions while being fully or partiallyimplemented and/or deployed as part of a wired and/or wirelesscommunication network in order to test other devices within thecommunication network. The one or more emulation devices may perform theone or more, or all, functions while being temporarilyimplemented/deployed as part of a wired and/or wireless communicationnetwork. The emulation device may be directly coupled to another devicefor purposes of testing and/or performing testing using over-the-airwireless communications.

The one or more emulation devices may perform the one or more, includingall, functions while not being implemented/deployed as part of a wiredand/or wireless communication network. For example, the emulationdevices may be utilized in a testing scenario in a testing laboratoryand/or a non-deployed (e.g., testing) wired and/or wirelesscommunication network in order to implement testing of one or morecomponents. The one or more emulation devices may be test equipment.Direct RF coupling and/or wireless communications via RF circuitry(e.g., which may include one or more antennas) may be used by theemulation devices to transmit and/or receive data.

One or more networks are described herein and, in embodiments, may referto one or more gNBs that may each be associated with one or moretransmission/reception points (TRPs) or any other node in a RAN.

The receiver of a WTRU may need to implement automatic frequency control(AFC) to maintain the frequency of its local oscillator tuned to theoscillator used at the transmitter side. This function may be supportedby various synchronization signals (SSs) and/or reference signals (RSs).Maintaining coarse AFC may be necessary for coherent detection of aphysical downlink control channel (PDCCH) and any incoming scheduled DLtransmissions. In LTE, coarse AFC may use the PSS/SSS synchronizationcodes that may be present every 5 ms and the CRS that may be present onat least 2 OFDM symbols per 1 ms interval. In NR, coarse AFC may use thesynchronization signal block (SSB), which may have a periodicity of atleast 20 ms. An NR device may also exploit a CSI-reference signal(CSI-RS) if configured and activated or a demodulation reference signal(DMRS), which may be present only during a DL transmission. A specialsignal, the tracking reference signal (TRS), may also be configured andactivated for an NR device to facilitate coarse AFC. The TRS may beconfigured as a non-zero power CSI-RS resource set with a recurrenceperiod of 10, 20, 40 or 80 ms. It may be present on three resourceelements (REs) in a resource block (RB) and in two OFDM symbols out of14 in two consecutive timeslots. A reduced density TRS only using thefirst timeslot may also be configurable.

FIG. 2 is a diagram 200 of an example of discontinuous reception (DRX).FIG. 2 shows a full DRX cycle 202 a and a portion of a second DRX cycle202 b. In the example illustrated in FIG. 2 , each DRX cycle 202 a, 202b includes an ON duration 204 a, 204 b and an OFF duration 206 a, 206 b.A WTRU may monitor a DL control channel, such as a PDCCH, during ONdurations 204 a, 204 b and enter a sleep state (e.g., not monitor thePDCCH) during OFF durations 206 a, 206 b. While only two DRX cycles 202a, 202 b are illustrated in FIG. 2 , a WTRU configured for DRX mayperiodically repeat the DRX cycle over any number of cycles.

As illustrated in the example of FIG. 2 , a WTRU may begin a DRX cyclewith an ON duration. An ON duration timer may be used to determine aconsecutive number of PDCCH occasions that that a WTRU may need tomonitor or decode, such as after wakeup from the DRX cycle or at thebeginning of a DRX cycle. A DRX inactivity timer may be used todetermine when to switch to the OFF duration. A DRX retransmission timermay be used to determine a consecutive number of PDCCH occasions tomonitor when retransmission is expected by the WTRU. A DRXretransmission timer may be used to determine a maximum duration until aDL retransmission or grant for UL retransmission may be received.

During OFF durations, such as OFF durations 206 a, 206 b, in addition tonot monitoring a DL channel, such as the PDCCH, a WTRU may not measureor report channel state information (CSI) in a subframe configured tomeasure and/or report a periodic CSI reporting. In embodiments, a WTRUmay need to monitor the PDCCH or PDCCH occasions during an active timethat may occur during an ON duration or an OFF duration. In otherembodiments, an active time may begin during an ON duration and continueduring an OFF duration. An active time may include the time during whichat least one of the following is true: any DRX timer, such as an ONduration timer, an inactivity timer, a retransmission timer, or a randomaccess contention resolution timer, is running; a scheduling request issent (e.g., on the physical uplink control channel (PUCCH); and a PDCCHindicating a new transmission addressed to the cell radio networkidentifier (C-RNTI) of a MAC entity of the WTRU has not been receivedafter successful reception of a random access response for a randomaccess preamble not selected by the MAC entity among thecontention-based random access preambles.

A DRX cycle, such as DRX cycles 202 a, 202 b, may be a short DRX cycleor a long DRX cycle. In embodiments, a WTRU may use a short DRX cyclefor a period of time and then a long DRX cycle. A DRX inactivity timermay be used to determine a time duration (e.g., in terms of transmissiontime interval (TTI) after a PDCCH occasion in which a successfullydecoded PDCCH indicates a UL or DL user data transmission. A PDCCHoccasion may be a time period that may contain a PDCCH, such as asymbol, a set of symbols, a slot, or a subframe. A DRX short cycle maybe the first DRX cycle that a WTRU enters after expiration of the DRXinactivity timer. The WTRU may be in the short DRX cycle until theexpiration of a DRX short cycle timer. When the DRX short cycle timer isexpired, the WTRU may use a long DRX cycle. The DRX short cycle timermay be used to determine the number of consecutive subframes that mayfollow the short DRX cycle after the DRX inactivity timer has expired.

In RRC connected mode, a WTRU may use connected mode DRX (C-DRX). Whenan LTE or NR device is in C-DRX, it may be configured with a DRX cycle.Configuration of separate short and long DRX cycles is possible. TheC-DRX cycles may be set in the range of several ten to several hundredsof milliseconds. A WTRU may wake up at determined time instants, such asduring the DRX ON duration, and attempt to decode the PDCCH in the firsttimeslot of the DRX ON duration. If no message is received or decoded inthe timeslot, the WTRU may decrease a configurable ON duration counterand may again attempt to decode the PDCCH in the next PDCCH monitoringopportunity on an active CORESET and for the configured search spaces.When the counter reaches zero, the WTRU may return to a sleep state andwill not attempt to decode a PDCCH again until the next DRX ON duration.

To be able to decode the PDCCH at the beginning (e.g., the firsttimeslot) of a C-DRX ON duration, a WTRU may need to have achieved atleast coarse AFC. The DMRS contained inside the RBs of the activebandwidth part (BWP) carrying the PDCCH for the device may only beexploited to fine-tune AFC during ongoing reception of that PDCCH andfor subsequent timeslots. In LTE, a WTRU may achieve coarse AFC bywaking up a short period of time before the start of a DRX ON durationand measuring the cell specific reference signal (CRS) available in mostsubframes.

In embodiments, wake-up signals (WUSs) and go-to-sleep signals (GOSs)may be used, for example, in conjunction with a DRX operation. A WUS/GOSmay be associated with one or more DRX cycles and may be transmittedand/or received prior to an associated time or part of an associated DRXcycle.

FIG. 3 is a diagram 300 of an example DRX cycle 302 with WUS and GOS. Inthe example illustrated in FIG. 3 , a WTRU may receive a WUS 308 and, inresponse, may wake up to monitor a downlink channel in the associated ONduration 304. In embodiments, a WTRU receiving a WUS may wake up andmonitor the downlink channel in ON durations for one or more DRX cycles.The WTRU may also receive a GOS 310 and, in response, may not monitorthe downlink channel in an associated OFF duration 306. In embodiments,a WTRU receiving a GOS may not monitor the downlink channel for one ormore DRX cycles and may remain in a sleep mode. In embodiments, either aWUS or a GOS, or both a WUS and a GOS, may be implemented.

In NR, a WTRU may be configured with one or more CSI resourceconfigurations, such as non-zero-power (NZP) CSI resources. Each CSIresource configuration may include one or more NZP-CSI-RS resource sets.Each NZP CSI resource set may include up to 64 NZP-CSI-RS resources. Atriggering offset for an aperiodic NZP-CSI-RS resource may be configuredper NZP-CSI-RS resource set. A WTRU may be further configured with oneor more CSI reporting configuration. Each CSI reporting configurationmay be associated with a CSI resource configuration for channelmeasurement. An associated BWP-ID and resource type (e.g., aperiodic,periodic, or semi-persistent) may be configured per CSI resourceconfiguration.

FIG. 4 is a diagram 400 of example CSI resource and CSI reportingconfigurations and shows the association between various NZP-CSI-RSresources, NZP-CSI-RS resource sets, CSI resource configurations, andCSI reporting configurations. In the example illustrated in FIG. 4 , aWTRU is configured with eight NZP-CSI-RS resources 401, 402, 403, 404,405, 406, 407 and 408. The ellipsis in FIG. 4 , however, indicates thata WTRU may be configured with any number of NZP-CSI-RS resources.NZP-CSI-RS resource 401 includes resource set 410, NZP-CSI-RS resource402 includes resource set 411, NZP-CSI-RS resource 403 includes resourcesets 410 and 411, NZP-CSI-RS resources 404 and 405 each includesresource set 412, and NZP-CSI-RS resources 406, 407 and 408 eachincludes resource set 413. The resource set 410 may have anAP-triggering offset of 0, and the resource set 411 may have anAP-triggering offset of 4. The remaining resource sets (e.g., 412 and413) may also be configured with different AP-triggering offsets.

The resource sets 410 and 411 may be associated with CSI resourceconfiguration 420, the resource set 412 may be associated with CSIresource configuration 421, and the resource set 413 may be associatedwith the CSI resource configuration 422. The CSI resource configuration420 may be for an aperiodic resource type and BWP-ID 0, the CSI resourceconfiguration 421 may be for a periodic resource type and BWP-ID 0, andthe CSI resource configuration 422 may be for a semi-persistent resourcetype and BWP-ID 2. The CSI resource configuration 420 may be associatedwith CSI reporting configurations 430, 431 and 433, the CSI resourceconfiguration 421 may be associated with the CSI reportingconfigurations 432 and 434, and the CSI reporting configuration 422 maybe associated with the CSI reporting configuration 435.

A WTRU may receive an aperiodic CSI request in a slot n, and itsassociated aperiodic CSI-RS (or NZP-CSI-RS) resource set may be locatedin a slot n+x, where x may be at least one of {0, 1, 2, 3, 4}. Table 1below shows an example of a CSI request field and its associatedreporting and resource settings.

TABLE 1 CSI request Slot offset of the field in DCI Associated reportingsetting Associated associated NZP- (up to 64 (each reporting setting mayinclude aperiodic NZP-CSI- CSI-RS resource states) up to 16 reportingconfigurations) RS resource set ID set 000 — — — 001 Reportingconfiguration #1  1 0 010 Reporting configuration #2  2 0 . . . . . . .. . Reporting configuration #x  2 1 011 Reporting configuration #k  0 3Reporting configuration #k + 1  0 3 . . . . . . . . . . . . 110Reporting configuration #y  0 0 111 Reporting configuration #x 15 1

Each CSI request field may be associated with a reporting setting (orCSI associated report configuration information), and the reportingsetting may include up to 16 reporting configurations. Each reportingconfiguration may be considered as a CSI reporting configuration. On acondition that more than one aperiodic NZP-CSI-RS resource set isassociated with a reporting configuration, a single aperiodic NZP-CSI-RSresource set may be selected for the CSI request field. Each aperiodicNZP-CSI-RS resource set may be configured with a slot offset value fromthe slot where a WTRU received the CSI request.

In NR, a WTRU may be configured with a set of slot offsets for physicaldownlink shared channel (PDSCH) scheduling from the slot where the WTRUreceived scheduling DCI. A WTRU may be configured withPDSCH-TimeDomainResourceAllocationList (or PDSCH-TDRA list), which mayinclude up to a number (e.g., 16) of PDSCH-TDRA configurations. EachPDSCH-TDRA configuration may include: a slot offset value (e.g., k0)which may be, for example one of {0, 1, . . . , 32}, a mapping typewhich may be, for example one of {typeA, typeB}, and/or a startingsymbol and length (e.g., SLIV) which may be, for example one of {0, 1, .. . , 127}. The k0 value may determine the slot offset for the PDSCHreception from the slot where the scheduling DCI is received. Forexample, if a WTRU receives the DCI for a PDSCH in a slot #n, it mayreceive the PDSCH in the slot #n+k0. The mapping type may determine theslot length. For example, type A may be used for a normal slot lengthand type B may be used for a sub-slot length. The SLIV may determine thestarting symbol and the length of the PDSCH within a slot. In theexamples and embodiments described herein, PDSCH may be replaced byPUSCH and slot offset k0 may be replaced by slot offset k2. For example,A WTRU may be configured with PUSCH-TimeDomainResourceAllocationList (orPUSCH-TDRA list), which may include up to a number (e.g., 16) ofPUSCH-TDRA configurations. Each PUSCH-TDRA configuration may include: aslot offset value (e.g., k2) which may be, for example one of {0, 1, . .. , 32}, a mapping type which may be, for example one of {typeA, typeB},and/or a starting symbol and length (e.g., SLIV) which may be, forexample one of {0, 1, . . . , 127}. The k2 value may determine the slotoffset for the PUSCH transmission from the slot where the scheduling DCIis received.

The receiver of a wireless communication device may be equipped withmultiple RF chains. Each such chain may include one or more antennaelements plus analog circuitry (e.g. low-noise amplifier, filters,oscillator, mixer, and/or analog-to-digital converter). Reception usingmultiple RF chains may increase performance through diversity and/orspatial processing. Minimum performance requirements for RF sensitivityassume that a WTRU is equipped with a minimum number of Rx antennaports.

For operation in frequency range 1 (below 6 GHz), many NR devices willuse four Rx RF chains for reception of DL signals and channels from thegNB to, for example, provide robust link performance and efficientlyexploit spatial multiplexing to achieve high DL spectral efficiency.Minimum reception requirements using the assumption of four Rx RF chainsmay be set for several NR operating bands. Specialized types of NRdevices, such as those intended for V2X type of applications, may beexpected to only use two Rx RF chains. Dual-mode LTE/NR devices sharingcommon RF may also be expected to follow LTE requirements for DLreception. For operation in frequency range 2 (mmWave), many NR deviceswill implement analog beamforming support by using multiple RF panels.Among other advantages, beamforming may allow for improved link budgetswhen operating at mmWave frequencies.

In existing NR technology, similar to LTE, the number of Rx antennas touse by a device for DL reception is dependent on the operating band.Device performance requirements may be set by assuming the availabilityof the mandated number of device Rx antennas. A device may advertisesupport for a set of LTE or NR operating bands to the network, possiblyin conjunction with supported band combinations for carrier-aggregationor dual-connectivity. This may implicitly indicate the support of themandated number of Rx chains on the device for the operating band.

Power consumption for active RF components, such as oscillators, lownoise amplifiers (LNAs) and analog-to-digital (A/D) converters may scalelinearly with the number of active Rx chains in a device. The digitalbaseband (BB) may implement low-level functions such as channel samplebuffering, spatial layer de-mapping and channel estimation. Powerconsumption in the low-level digital BB may also increase with thenumber of active Rx paths. Other high-level functions in the digital BB,such as transport channel processing and channel decoding, may see anincrease in power consumption in the presence of reception usingmultiple active RF chains in the device, but primarily as a function ofthe transmitted data rate, which may be high even with a lower number ofRx chains if the signal to interference and noise ratio (SINR) is goodenough.

WTRU power consumption is expected to increase in NR and beyond ashigher carrier frequencies, wider bandwidths and advanced MIMO schemesare deployed. For example, transceiver circuitry, including RF chains,consumes a considerable amount of power, for example as compared tobaseband processing. Even when configured with C-DRX, data may not bereceived for a significant period of time while a WTRU is monitoring thePDCCH during active time. As a result, a WTRU equipped with multiplereceive (Rx) chains may waste a significant amount of power attemptingto receive while no data is being transferred. If a WTRU implementationattempts to save power by turning off some Rx chains during active time,there is risk that the WTRU may fail to meet performance requirementsbecause the network may assume that it is always prepared to receive thePDCCH and PDSCH using all Rx chains. Conventional power savingmechanisms do not allow dynamic turn on and off of RF chains or otherparts of the transceiver circuitry. Embodiments are described hereinthat may allow a WTRU to safely reduce its number of Rx chains whenpossible without impacting performance.

Additionally, signals needed to achieve coarse AFC may not be generallyavailable just before the start of a WTRU's on-duration. As a result, anNR WTRU may need to wake up in between on-durations for the sole purposeof detecting the appropriate signals (e.g. SSB). This may be lessefficient than the WTRU just before the beginning of an ON duration whenconsidering practical transition times for switching the relatedcircuitry on and off. Embodiments are described herein that may enablemaintenance of coarse AFC while reducing the number of wake-up intervalsnot related to the actual DRX ON duration.

Further, in, for example, R15 NR, DRX may be configured with, at most, asingle DRX configuration. The sleep opportunity is purely based on timedomain. Further, the WTRU may spend a considerable amount of timemonitoring the PDCCH without being scheduled. In R15, during the ONduration, the WTRU is required to monitor all CORESETs and all searchspaces in the active BWP each ON duration, which may result in asignificant number of blind decodes and consume a substantial amount ofdevice power. A potential tool to reduce the number of blind decodesusing the R15 framework may be to configure the default BWP with asingle search space, given that a WTRU in DRX is likely to be in thedefault BWP due to the expiry of the inactivity timer, and rely onsending a DCI with a BWP switch upon scheduling the WTRU during a givenON duration. However, given that the RACH and SR functionalities rely onthe default BWP, and given that the WTRU may resort to the default BWPif the BWP inactivity timer is short, the scheduling capacity may belimited if the default BWP is limited to one search space or oneCORESET. Embodiments are described herein that may address this.

Embodiments described herein provide for a number of different radioperformance states, radio performance modes, power modes, ortransmission modes. One of ordinary skill in the art will understandthat these or similar terms may be used interchangeably throughout. Inembodiments, a WTRU may be configured to operate according to one of aset of possible radio performance states, radio performance modes, powermodes, or transmission modes. A radio performance state, radioperformance mode, power mode, or transmission mode may, for example,determine a set of maximum performance metrics and/or capabilitiesapplicable to the WTRU at a given point in time.

As described above, a WTRU may be configured with a set of PDSCH-TDRA(e.g., a PDSCH-TDRA list). A WTRU may receive an indication of one ofthe PDSCH-TDRA in a DCI for PDSCH scheduling. If the indicatedPDSCH-TDRA is k0=0, for example, excess WTRU power consumption may berequired as the WTRU may need to buffer the PDSCH region in a slot wherethe PDCCH is monitored for a DCI with C-RNTI or configured schedulingRNTI (CS-RNTI).

In some embodiments, a power mode may determine which subset ofPDSCH-TDRA entries in the configured PDSCH-TDRA list may be valid orpresent in the associated DCI for a PDSCH scheduling. For example, if aWTRU is in a first power mode (e.g., normal mode), the WTRU may assumethat all PDSCH-TDRA entries in the PDSCH-TDRA list may be used when theWTRU monitors a PDCCH in a slot. If a WTRU is in a second power mode(e.g., power saving mode), the WTRU may assume that the PDSCH-TDRAentries with k0=0 may be not used when the WTRU monitors a PDCCH in aslot or the WTRU may ignore the PDSCH-TDRA entries with k0=0

In some embodiments, a power mode may determine which subset ofaperiodic CSI reporting trigger states in a configured CSI reportingtrigger state list may be valid (or present) in the associated DCI foraperiodic CSI reporting. For example, if a WTRU is in a first powermode, the WTRU may assume or expect that all CSI reporting triggerstates in the configured CSI reporting trigger state list may be validwhen the WTRU monitors a PDCCH for aperiodic CSI reporting. If a WTRU isin a second power mode, the WTRU may assume or expect that the CSIreporting trigger states associated with an aperiodic NZP-CSI-RSresource set with slot offset less than a threshold may be invalid. Asused herein, invalid and unusable, in the context of a CSI reportingtrigger, may be used interchangeably, and unusable is an example ofinvalid. In some embodiments, the threshold value (Ttre) may be apredefined number, such as ‘1’. In some embodiments, the threshold valuemay be determined based on numerology. For example, a first thresholdvalue may be used for a first subcarrier spacing (e.g., Ttre=1 for 15kHz SCS), and a second threshold value may be used for a secondsubcarrier spacing (e.g., Ttre=3 for 60 kHz SCS).

In some embodiments, a power mode may determine a minimum slot offsetvalue of NZP-CSI-RS resource sets associated with one or more configuredaperiodic CSI reporting trigger states. In some embodiments, a powermode may determine the maximum transmission rank and/or maximummodulation order for a PDSCH. For example, if a WTRU is in a first powermode, the WTRU may expect to receive the PDSCH with a maximumtransmission rank (R_(max)) and/or a maximum modulation order (M_(max))based on the WTRU's capability when the WTRU monitors an associatedPDCCH in a slot. If a WTRU is in a second power mode, the WTRU mayassume or expect to receive the PDSCH with a limited maximumtransmission rank (R_(limit), R_(max)>R_(limit)) and/or limited maximummodulation order (M_(limit), M_(max)>M_(limit)) when the WTRU monitorsan associated PDCCH in a slot.

In some embodiments, a power mode may determine a set of aggregationlevels and/or a number of candidates for an aggregation level. Forexample, if a WTRU is in a first power mode, the WTRU may monitor allaggregation levels and/or its associated number of candidates configuredfor a search space. If a WTRU is in a second power mode, the WTRU maymonitor a subset of aggregation levels and/or number of candidatesconfigured for a search space. In such embodiments, the subsetdetermined based on a first N entry of the decoding candidate for eachconfigured aggregation level may be monitored. N may be a predefinednumber, configured via a higher layer signaling, or determined by theWTRU. Alternatively or additionally, in such embodiments, a maximumaggregation level within configured aggregation levels may be monitoredby the WTRU.

In some embodiments, a power mode may determine an operating frequencybandwidth (e.g., a bandwidth of the active BWP). For example, if a WTRUis in a first power mode, the WTRU may monitor the PDCCH in a first BWP,and if the WTRU is in a second power mode, the WTRU may monitor thePDCCH in a second BWP. The first BWP may be wider than the second BWP.

In some embodiments, a power mode may be determined based on the searchspace type or ID. In an example, a first power mode may be used in afirst search space type (e.g., any common search space associated withCORESET #0) and a second power mode may be used in a second search spacetype (e.g., WTRU-specific search space). In another example, a firstpower mode may be used in a first search space (e.g., search space IDsnot associated with a second power mode), and a second power may be usedin a second search space for which search space IDs may be configured.Alternatively, the search space IDs for the second power mode may beimplicitly determined based on search space IDs associated with aspecific CORESET. For example, search spaces associated with CORESET #xmay be determined for the second power mode, where the value x may beconfigured via a higher layer signaling or be predetermined (e.g., 0).Additionally or alternatively, the search space IDs for the second powermode may be implicitly determined based on search space IDs used for aspecific RNTI. For example, search spaces for power saving RNTI(PS-RNTI) may be determined for the second power mode, where PS-RNTI maybe for the uplink and downlink shared channel (e.g., PDCCH and PUSCH).

In some embodiments, the power mode may be determined based on thesearch space configuration parameters. In one example, the power modemay be determined based on the periodicity of the search space. Forexample, a first power mode may be used if the periodicity of a searchspace is longer or shorter than a threshold, and a second power may beused if the periodicity of a search space is shorter or longer than thethreshold. The threshold value may be predetermined or configured viahigher layer signaling. In another example, the power mode may bedetermined based on aggregation level set (or minimum aggregation level,or maximum aggregation level) configured for the search space.

In some embodiments, the power mode may be configured via a higher layersignaling. In other embodiments, the power mode may be indicated by anassociated power saving signal, which may indicate whether a WTRU needsto monitor associated PDCCH monitoring occasions or not.

In some embodiments, the power mode may be determined based on WTRU RRCstatus, which may include RRC idle, RRC connected, and RRC inactive. Thefirst power mode and the second power mode may be used for RRC connectedwhile the first power mode may only be used for RRC idle and RRCinactive.

In some embodiments, the power mode may be determined based on thePDSCH-TDRA entries in the configured PDSCH-TDRA list. For example, ifthe minimum k0 value of the PDSCH-TDRA entries in the configuredPDSCH-TDRA list is less than a threshold, a first power mode may beused. Otherwise, a second power mode may be used. In some embodiments,the threshold value (Ttre) may be ‘1’. If one or more of PDSCH-TDRAentries in the configured PDSCH-TDRA list include k0=0, a WTRU may use afirst power mode. If all PDSCH-TDRA entries in the configured PDSCH-TDRAlist have k0>0, a WTRU may use a second power mode. In otherembodiments, the threshold value may be determined based on numerology.For example, a first threshold value may be used for a first subcarrierspacing (e.g., Ttre=1 for 15 kHz SCS), and a second threshold value maybe used for a second subcarrier spacing (e.g., Ttre=3 for 60 kHz SCS).In some embodiments, the power mode may be determined per bandwidth part(BWP), cell, search space, CORESET, and/or physical channel.

In some embodiments, the minimum slot offset (e.g., minimum k0) valuefor PDSCH-TDRA entries in the configured PDSCH-TDRA list may berestricted dynamically. For example, a power saving signal may indicatea threshold value for the minimum k0 value for the PDSCH-TDRA entries inthe configured PDSCH-TDRA list, and a WTRU may ignore the PDSCH-TDRAentries associated with k0 values smaller than the threshold. Forexample, a WTRU may ignore a (e.g., any) PDSCH-TDRA entry associatedwith a k0 value smaller than the threshold.

A WTRU ignoring one or more PDSCH-TDRA entries may mean that the WTRUmay not expect to receive such entries, a WTRU may not buffer a PDSCHregion of the slots less than the threshold from the slot for the PDCCHmonitoring, and/or a WTRU may not receive a PDSCH in the slots less thanthe threshold from the slot for the PDCCH monitoring.

A WRTU may receive or monitor the power saving signal in predefined orpredetermined time location(s) which may be associated with one or morePDCCH monitoring occasions.

A power saving signal may be at least one of a DCI, a reference signal,and/or a preamble.

k0 and k2 are used herein as examples of an offset (e.g., a slotoffset). Other parameters may be used and still be consistent with theexamples and embodiments described herein. Other offsets such as symboloffsets may be used and still be consistent with the examples andembodiments described herein.

FIG. 5 is a flow diagram of an example method 500 of WTRU power saving.In the example illustrated in FIG. 5 , a wireless transmit/receive unit(WTRU) may receive a TDRA list configuration (502). The TDRA listconfiguration may include multiple entries. Each of the entries mayinclude a resource allocation that may include a slot offset value thatmay be, for example, for locating a slot in which to receive the PDSCH(or transmit the PUSCH). In embodiments, each of the entries in the TDRAlist may include a mapping type and/or a startSymbolAndLength parameter,as described in more detail above.

The WTRU may receive physical layer or layer 1 (L1) signaling, which mayinclude a minimum slot offset value (504). In embodiments, the physicallayer or L1 signaling may be used to dynamically provide the WTRU with aminimum slot offset value. The WTRU may, for example when scheduled forPDSCH (or PUSCH), decode a DCI in or on a slot on the PDCCH (506). TheWTRU may obtain, from the decoded DCI, an index identifying one of theentries in the TDRA list (508). The WTRU may retrieve, from the TDRAlist, a particular slot offset value identified by the index (510).

The WTRU may compare the particular slot offset value with the minimumslot offset value, for example, that was received in the physical layeror L1 signaling (512). If the particular slot offset value is less thanthe minimum offset value (514), the WTRU may determine that the entry inthe TDRA list identified by the index is invalid (516). In embodiments,if the WTRU determines an entry is invalid, the WTRU may not (e.g., doesnot) receive or buffer the scheduled PDSCH (or transmit the scheduledPUSCH), for example, in a slot offset from the slot on which the DCI wasdecoded where the slot offset may be the particular slot offset value.If, however, the WTRU determines that the particular slot offset valueis greater than or equal to the minimum slot offset value (514), theWTRU may proceed to receive the scheduled PDSCH (or transmit thescheduled PUSCH), for example in the slot offset from the slot which theDCI was decoded (518) where the slot offset may be the particular slotoffset value

The embodiments described above are described with respect to the PDSCH.However, one of ordinary skill in the art will understand that the sameor similar methods may be used for the PUSCH. In embodiments, theminimum slot offset may correspond to a particular radio performancestate and, when the WTRU is in a particular radio performance state, itmay attempt decoding of the PDSCH or transmitting the PUSCH only if theindicated slot offset (e.g., k0 and/or k2) which may be obtained fromthe DCI is greater than or equal to the minimum value (e.g., k0minand/or k2min) applicable to the current radio performance state. Inembodiments, a minimum value (e.g., k0min or k2min) may be applicableonly if the PDCCH is decoded in certain time symbols of the slot or theCORESET. For example, the value may be applicable if the PDCCH isdecoded in the last three symbols of a slot. In embodiments, the minimumslot offset (e.g., AP-trigger offset) for NZP-CSI-RS resource setsassociated with aperiodic CSI reporting trigger states may be limited ordetermined based on the minimum slot offset (e.g., k0) of the PDSCH-TDRAin the PDSCH-TDRA list at least in the same BWP. For example, if theminimum k0 value is n1 (e.g., n1=1) in the configured PDSCH-TDRA list,the minimum AP-trigger-offset value may be or may be limited to n2(e.g., n2=1), where n1 and n2 may be the same values or differentvalues.

If the minimum k0 value is determined for a BWP, a WTRU may not expectthat the minimum AP-trigger-offset value is smaller than a threshold(e.g., the minimum k0 value) for the same BWP. If the minimum k0 valueis determined for a BWP, a WTRU may ignore or not expect to receive CSIreporting trigger states associated with NZP-CSI-RS resource sets withAP-trigger-offsets smaller than a threshold (e.g., the minimum k0 value)for the same BWP. Ignoring a CSI reporting trigger state may imply thata WTRU may not report CSI for the triggered CSI reporting trigger state.If the minimum k0 value is determined for a BWP, a WTRU may ignore theCSI reporting configurations associated with NZP-CSI-RS resource setswith AP-trigger-offsets smaller than a threshold (e.g., the minimum k0value) in the triggered CSI reporting trigger state for the same BWP. ACSI reporting trigger state may include or correspond to one or more CSIreporting configurations, and each CSI reporting configuration may beassociated with an NZP-CSI-RS resource set. A WTRU may report CSIreporting configurations which are associated with NZP-CSI-RS resourcesets with AP-trigger-offsets larger than or equal to the threshold(e.g., minimum k0 value).

Reporting a CSI reporting configuration may correspond to reporting CSIfor the reporting configuration. Reporting a CSI reporting configurationmay correspond to reporting CSI for, based on (e.g., based onmeasurement of), and/or using the associated NZP-CSI-RS resource set.

In other embodiments, the minimum AP-trigger-offset value of anNZP-CSI-RS resource set for CSI reporting configurations (or aperiodicCSI reporting trigger states) may be dynamically restricted. Forexample, a power saving signal may indicate a threshold value for theminimum AP-trigger-offset value for the CSI reporting configurations (oraperiodic CSI reporting trigger states), and a WTRU may ignore a CSIreporting configuration (or aperiodic CSI reporting trigger state)associated with an NZP-CSI-RS resource set with an AP-trigger-offsetvalue smaller than the threshold.

An AP-trigger offset may be an aperiodic trigger offset that may be aslot offset. An AP-trigger offset may be an offset for DL reception orUL transmission. An AP-trigger offset may be an offset from the slot (orother time) of PDCCH reception of the AP-trigger to an RS resource set.An RS resource set may be used for (e.g., may be, may include, or mayidentify the time and/or frequency resources for) reception and/ormeasurement (e.g., of a RS). An RS resource set may be used for (e.g.,may be, may include, or may identify the time and/or frequency resourcesfor) transmission (e.g., of an RS). A CSI-request is an example of anAP-trigger. An SRS request is an example of an AP-trigger.

NZP-CSI-RS is an example of an RS. Another RS may be used and still beconsistent with the examples and embodiments described herein. AnNZP-CSI-RS resource set is an example of an RS resource set Another RSresource set may be used and still be consistent with the examples andembodiments described herein. SRS is another example of an RS for whicha minimum offset may apply and may be used to restrict SRS transmissionto AP-trigger offsets greater than or equal to the minimum offset.

A WTRU that is provided with a k0min, k2min and/or minimum aperiodicCSI-triggering offset may receive, for example in a data scheduling DCI,a k0, k2 and/or an aperiodic CSI-triggering offset that is smaller thanthe indicated minimum corresponding value. In some embodiments, when aWTRU receives a k0, k2 and/or aperiodic CSI-triggering offset that issmaller than the indicated minimum corresponding value in slot n, theWTRU may set the respective k0min, k2min and/or the minimum aperiodicCSI-triggering offset to a value (e.g. a configured or default valuesuch as 0). The WTRU may set or apply an updated value after (e.g, assoon as) decoding of the scheduling DCI is completed, for example inslot n or a later slot.

In some embodiments, a WTRU may be provided with the value of theminimum slot offset (k0min and/or k2min) and/or minimum aperiodic CSI-RStriggering offset. In such embodiments, if the WTRU receives a DCI,e.g., a downlink grant with a time domain resource assignment pointingto a PDSCH TDRA table entry with k0<k0min, or an uplink grant with atime domain resource assignment pointing to a PUSCH TDRA table entrywith k2<k2min, or an uplink grant with a CSI request pointing to a statein the CSI-AperiodicTriggerStateList that indicates an aperiodictriggering offset smaller than the minimum aperiodic triggering offset,then the WTRU may set the minimum aperiodic triggering offset (e.g.,k0min and/or k2min) to a value (e.g., a configured or default value).The value may be zero. The WTRU may expect to receive a DCI (e.g., ascheduling DCI such as a DL grant and/or a UL grant) with a time domainresource allocation pointing to any entry in the PDSCH or PUSCH TDRAtable. The WTRU may apply the new value of the minimum aperiodictriggering offset (e.g., k0min and/or k2min) in the slot where the DCIis received, or it may apply the new value in a slot later than when thenew value was received.

Additionally or alternatively, in embodiments where a WTRU may beprovided with the value of the minimum slot grant with a time domainresource assignment pointing to a PDSCH TDRA table entry with k0<k0min,or an uplink grant with a time domain resource assignment pointing to aPUSCH TDRA table entry with k2<k2min, or an uplink grant with a CSIrequest pointing to a state in the CSI-AperiodicTriggerStateList thatfurther indicates an aperiodic triggering offset smaller than theminimum aperiodic triggering offset, then the WTRU may set the minimumaperiodic CSI-RS triggering offset to a value (e.g., a configured ordefault value). The value may be zero. The WTRU may expect to receive aDCI (e.g., a scheduling DCI such as a UL grant) with a CSI requestpointing to any state in the CSI-AperiodicTriggerStateList. The WTRU maymeasure the CSI-RS according to the indicated state ofCSI-AperiodicTriggerStateList. If the WTRU receives the PDCCH anddecodes the DCI by the time the first OFDM symbol of the slot with theCSI-RS resources is received, the WTRU may measure the CSI-RS andfeedback the indicated CSI report. The WTRU may also drop the CSI reportindicated in the scheduling DCI if it cannot prepare the report.

In the above methods, the default values for k0min, k2min, and minimumaperiodic triggering offset may be the minimum of the all k0, all k2,and all aperiodic triggering offset, respectively, as configured by theRRC in the corresponding lists. In some embodiments, the embodimentsdescribed in the two immediately preceding paragraphs may be similarlyapplicable when the WTRU initiates a random access by transmitting arandom access preamble and when the WTRU switches to a new BWP.

In some embodiments, a DCI may be used to both schedule data andindicate to the WTRU to perform at least one power saving technique. Forexample, a DCI may schedule data and indicate to the WTRU a k0min valueusing at least 1 bit within the DCI.

In some embodiments, there may be at least two configurations of a DCI,and the configurations may have the same number of bits. For example,DCI Format 1_1 may be configured to have N bits, and, in the firstconfiguration, m (e.g. m=2) of the N bits may be configured to indicateto the WTRU the bandwidth part, and, in the second configuration, thesame m bits may be configured to indicate to the WTRU the value ofk0min.

In some embodiments, separate search space configurations may be used bythe WTRU to interpret the contents of the DCI. At least one search spaceconfiguration per DCI configuration may be used.

A WTRU may interpret the attribute indicated by the m bits (e.g.,whether the bits indicate an index of a BWP or k0min) based on whichtime (slot index and/or OFDM symbol(s) indices within the slot) thePDCCH containing the DCI is received. The search space configurationparameters configuring the monitoring slot and slot offset and/or themonitoring symbols within the slot may be used to indicate the time.Further, the WTRU may be configured with two search spaces, and eachsearch space configuration may have the same DCI format and a differentmonitoringSlotPeriodicityAndOffset parameter. For example, the WTRU maymonitor the configured CORESET (e.g. CORESET #1) every p1 slots, and, ifa PDCCH is detected, the DCI may indicate the BWP. Further, the WTRU maymonitor the configured CORESET every p2 slots, and, if a PDCCH isdetected, the DCI may indicate k0min.

Alternatively, the WTRU may interpret the attribute indicated by the mbits (e.g., whether the bits indicate an index of a BWP or k0min) basedon which CORESET the PDCCH containing the DCI is received. The searchspace configuration parameter configuring the CORESET may be used toindicate the control resource elements on which the PDCCH is received.Further, the WTRU may be configured with two search spaces. Each searchspace configuration may have the same DCI format and a differentcontrolResourceSetId parameter. For example, the WTRU may monitor afirst configured CORESET (e.g. CORESET #1), and, if a PDCCH is detected,the DCI may indicate the BWP. Further, the WTRU may monitor a secondconfigured CORESET (e.g. CORESET #2), and, if a PDCCH is detected, theDCI may indicate k0min.

In other embodiments, a combination of at least two of themonitoringSlotPeriodicityAndOffset, monitoringSymbolsWithinSlot, andcontrolResourceSetId search space configuration parameters may be usedto interpret the contents of the received DCI.

In other embodiments, at least one parameter in the search spaceconfiguration may be used to interpret the contents of the received DCI.Here, the DCI is the DCI configured in that search space. A first BWPmay be configured with a TDRA table by RRC, and the k0min/k2minapplicable to the TDRA table for the first BWP may be changeddynamically with L1 signaling. When a WTRU operating in the first BWPreceives an indication to switch to a second BWP, the WTRU may set thek0min/k2min values applicable to the TDRA table for the first BWP to thevalues indicated in the TDRA table configured by the RRC. For example, aTDRA table configured by the RRC for the first BWP may contain k0min=0slots, and the k0min value may be set to 1 slot by L1-signaling. Whenthe WTRU switches to the second BWP, the k0min applicable to the TDRAtable for the first BWP may be set to the value that had been indicatedby the RRC, i.e., 0 slots. In other words, all entries of the TDRA tableapplicable to the first BWP may be usable again. When the WTRU switchesback to the first BWP, all entries of the TDRA table applicable to thefirst BWP are usable.

In embodiments, a WTRU may receive or monitor a power saving signal,such as the L1 signaling described with respect to FIG. 5 , inpredefined or predetermined time locations that may be associated withone or more PDCCH monitoring occasions. In embodiments, a power savingsignal may be DCI, a reference signal and/or a preamble. In embodiments,the power saving signal may be PHY signaling, RRC signaling, MAC or MACCE. A value of k0min may be configured for each bandwidth part (BWP). Insuch embodiments, the applicable value may be that of the active BWP inwhich the PDCCH is decoded. Additional alternatives for the power savingsignal are described below with respect to how a WTRU may determine aradio performance state.

In embodiments, a radio performance state may include at least onereference sensitivity level. Additionally or alternatively, a radioperformance state may include a maximum TBS, rank, modulation order orcoding rate for PDSCH decoding or PUSCH transmission and/or a set ofpossible PDSCH mapping types. Additionally or alternatively, a radioperformance state may include a set or maximum number of BWPs or activeBWPs that can be operated on. Additionally or alternatively, a radioperformance state may include a maximum number or a set or subset of(per BWP, CC or WTRU) active TCI states for PDCCH, active TCI states forPDSCH, one port or two ports NZP-CSI-RS resources for beam management(e.g. CRI/RSRP, SSBRI/RSRP), NZP CSI-RS or SSB resources for CSIreporting, NZP CSI-RS or SSB resources for RRM measurements, periodicCSI reports, semi-persistent CSI reports or aperiodic CSI reportsettings, CSI reports that the WTRU can simultaneously process, TRSresource sets that the WTRU can simultaneously track, CSI-RS or SSBresources for PDCCH quality monitoring, CSI-RS/SSB resources for newbeam identifications, and/or RSRP values for non-group based RSRPreporting.

In embodiments, a radio performance state may include a number, amaximum number or a set of CORESETs, PDCCH search spaces, PDCCHcandidates, PDCCH aggregation levels, DCI formats, and/or monitoredPDCCH occasions within a CORESET or pattern thereof for PDCCH monitoring(per BWP, CC or WTRU) and/or whether PDCCH repetition may be used forPDCCH monitoring. Additionally or alternatively, a radio performancestate may include monitoring behavior, such as whether a certain RS orSSB is expected to be received only during active time (or while certainDRX timers are running) or whenever they are configured to be occurring.Additionally or alternatively, a radio performance state may include alevel of WTRU processing and/or a DRX configuration, an aspect of a DRXconfiguration and/or a parameter configuration within a DRXconfiguration.

In embodiments, a radio performance state may include at least one ofthe following RRM requirements, such as defined in an evaluation periodfor radio link quality, a number of NR or inter-RAT frequency carriersthat can be monitored, a number of reporting criteria that may besupported in parallel, a number of intra-frequency, inter-frequency orinter-RAT cells that may be monitored, a latency for identification of anew detectable intra-frequency, inter-frequency or inter-RAT cell, ameasurement period, and/or an accuracy requirement for RRM measurements.Additionally or alternatively, a radio performance state may include aset of configured PDSCH-to-HARQ feedback timing indicators (k1) that maybe indicated by DCI. A minimum value k1min of the PDSCH-to-HARQ feedbacktiming may be configured. In such embodiments, a WTRU may transmit HARQfeedback, for example, only if the indicated k1 value is equal to orhigher than the minimum value k1min applicable to the current radioperformance state. An offset k1off of the PDSCH-to-HARQ feedback timingmay be configured. In such embodiments, the WTRU may apply aPDSCH-to-HARQ feedback timing corresponding to the sum of k1offapplicable to the radio performance state, and of the indicated k1value.

In embodiments, a radio performance state may include a set ofconfigured time domain relations between PDCCH and PDSCH that may beindicated by DCI, including, for example, a number of slots (k0) betweenPDCCH and PDSCH (e.g., cross-slot scheduling offset), a PDSCH mappingtype and a combination of start symbol and length of PDSCH. Additionallyor alternatively, a radio performance state may include an offset k0offof the number of slots k0 between PDCCH and PDSCH (or PUSCH). The WTRUmay determine that the number of slots between the PDCCH and PDSCHcorresponds to the sum of the indicated k0 value and of the offset k0offapplicable to the current radio performance state. The offset valuek0off may depend or may be applicable only if the PDCCH is decoded incertain time symbols of the slot or of the CORESET. For example, thevalue may depend on whether PDCCH is decoded in the last 3 symbols of aslot or in the first 4 symbols. The value of k0off for the radioperformance state may signaled by RRC or MAC CE. A value of k0off may beconfigured for each BWP. In this case, the applicable value may be thatof the active bandwidth part in which the PDCCH is decoded.

In embodiments, a radio performance state may include a number of RFchains, active antenna chains, RF panels and/or diversity branchesexpected for reception. Additionally or alternatively, a radioperformance state may include a number of antenna elements for MIMOand/or a MIMO algorithm.

WTRU power consumption may be improved from different implementationaspects when the WTRU operates in a radio performance state thatincludes reduced requirements or capabilities. For example, a WTRU maybe able to switch off one or more RF chains if it knows that therequired sensitivity level according to the current radio performancestate is relaxed to a certain value. The WTRU may also be able to switchoff certain antenna panels if the number of TCI states that are activeis reduced.

Similarly, a WTRU may be able to switch off one or more RF chains andpossibly some baseband components if it knows that the maximum transportblock size or rank for PDSCH will be below a certain value at least upto a known point in the future. For this to be effective, the allowedlatency before switching to a radio performance state corresponding to ahigher performance should be higher than the latency required to turn onthe necessary components in a practical implementation. Such minimumlatency may be an aspect of a radio performance state (or of atransition between states) and may be configured or pre-defined.

A WTRU receiver may implement or use one or more receiver components (orconfigurations, types), and each receiver component may have its owncapability (e.g., configuration). For example, a first receivercomponent may use a single RF chain, and a second receiver component mayuse multiple RF chains. In another example, a first receiver componentmay support QPSK as a maximum modulation order, and a second receivercomponent may support 256QAM as a maximum modulation order. The firstreceiver component may provide low peak throughput performance whileconsuming less power/energy, and the second receiver component mayprovide high peak throughput performance while consuming higherpower/energy. The first receiver component may consume less power/energythan the second receiver component.

A WTRU may use one receiver component at a time, or a WTRU may use a setor subset of receiver components at a time. A receiver component or setof receiver components may be configured as a WTRU receiver with acertain capability. Hereafter, a receiver component, set of receivercomponents, subset of receiver components, receiver configuration, Rxconfiguration, Rx component, receiver type, Rx type, receivercapability, and Rx capability may be used interchangeably. An RF chain,transmit and receive unit (TXRU), RF transceiver, and RF may beinterchangeably used.

In embodiments, a power or performance mode may determine one or morereceiver components that a WTRU may use. Each receiver component mayconsume a separate or different level of power or energy. For example, areceiver component (or set of receiver components) that may consume ahigh power/energy may correspond to a high power mode. A receivercomponent (or set of receiver components) that may consume a lowpower/energy may correspond to a low power mode. Low power mode, powersaving mode and power savings mode may be used interchangeably herein.High power mode, normal power mode and non-power saving mode may be usedinterchangeably herein. For another example, a receiver component or setof receiver components that may support a high peak throughput maycorrespond to a high performance mode. A receiver component or set ofreceiver components that may support a low peak throughput maycorrespond to a low performance mode.

In embodiments, a power or performance mode may be associated with oneor more transmission and/or reception (Tx/Rx) parameters. A Tx/Rxparameter may be determined or known by a WTRU. A Tx/Rx parameter may beconfigured, such as via signaling from a gNB. A WTRU may signal orreport a Tx/Rx parameter that the WTRU supports to a gNB. The WTRU maysignal or report a Tx/Rx parameter that the WTRU supports for eachreceiver component, set of receiver components, power mode, and/orperformance mode that the WTRU supports.

In embodiments, a Tx/Rx parameter may be a number of RF chains. A firstpower mode may use a first number of RF chains (e.g., 4), and a secondpower mode may use a second number of RF chains (e.g., 1) in a cell,carrier, or BWP. The number of RF chains used at a WTRU receiver may bereferred to as the maximum rank supported for a PDSCH reception. Forexample, if the supported maximum rank is X (e.g., 1 or 4), at least X(e.g., 1 or 4) RF chains may be used or active, such as for reception ina carrier/BWP. A first power mode may support a maximum rank 4, and asecond power mode may support a maximum rank 1.

The number of RF chains used at a WTRU receiver may be indicated,determined, or used based on the coverage level of the WTRU. A firstcoverage level may be associated with a first power mode, and a secondcoverage level may be associated with a second power mode. A coveragemode and a power mode may be interchangeably used.

A supported power mode may be indicated from or reported by a WTRU, suchas WTRU capability. For example, if a WTRU supports multiple power modes(e.g., normal and low or high, medium, and low), the WTRU may report thesupported power modes to a gNB. In another example the WTRU may reportthat it supports a low or power saving mode. The WTRU may report acapability (e.g., number of RF chains or maximum rank) associated with apower mode or coverage level. For example, the WTRU may report acapability it supports for each power mode and/or coverage level that itsupports. If a WTRU supports multiple power modes, the WTRU may reportthe supported power modes and their associated capabilities to a gNB.

In embodiments, a Tx/Rx parameter may be a receiver sensitivity level,which may be different based on the power mode. A WTRU may report itsreceiver sensitivity level based on the power mode.

In embodiments, a Tx/Rx parameter may be a supported maximum modulationorder (e.g., 256QAM), which may be determined, indicated, or reportedfor each power mode as a WTRU capability. A WTRU may indicate itscapability of maximum modulation order supported for each power mode. Amaximum modulation order and a maximum modulation coding scheme (MCS)level may be interchangeably used herein.

In embodiments, a Tx/Rx parameter may be a maximum supported RFbandwidth (e.g., 1 GHz). A maximum supportable bandwidth may bedetermined, indicated, or reported for each power mode as a WTRUcapability. A maximum RF bandwidth may be indicated as the maximumnumber of RBs supported for a PDSCH. Additionally or alternatively, aTx/Rx parameter may be at least one of a maximum number of carrierssupported (e.g., simultaneously with carrier aggregations), a maximumBWP size within a carrier (e.g., up to 275 RBs), and/or a maximum numberof BWPs supported for simultaneous reception. Additionally oralternatively, a Tx/Rx parameter may be a maximum number of beams (orbeam group) supported. A number of beams supported may be differentbased on the power mode. The number of beams may be the number of Rxbeams (or indicated as the number of SRS resources required for a beammanagement at a WTRU).

In embodiments, a Tx/Rx parameter may be a maximum coupling losssupported (e.g., coverage level). Additionally or alternatively, a Tx/Rxparameter may be a set of subcarrier spacings supported in a givenfrequency band (e.g., 15 kHz, 30 kHz, 60 kHz, 120 kHz). Additionally oralternatively, a Tx/Rx parameter may be at least one of a minimumHARQ-ACK timing supported for a set of scheduling parameters and/orconditions and a minimum timeline supported for a set of aperiodic CSIreporting configurations when it is triggered. Additionally oralternatively, a Tx/Rx parameter may be at least one of a channelestimation scheme, a precoding granularity for channel estimation ofDM-RS, a channel coding scheme (e.g., Turbo, LDPC, Polar, Convolutional,RM), and/or a MIMO receiver type (e.g., MMSE, ML). Additionally oralternatively, a Tx/Rx parameter may be a sleep mode (e.g., no sleep,deep sleep, partial sleep, light sleep). A wake-up time may bedetermined based on the sleep mode. The wake-up time may be a time(e.g., a time required) to start receiving a downlink signal (e.g.,PDCCH). A wake-up time, warm-up time, preparation time, and activationtime may be interchangeably used.

FIG. 6 is a diagram of an example WTRU 600 configured with multiplereceiver components that may correspond to different power modes. In theexample illustrated in FIG. 6 , the WTRU 600 includes two antennas 610and 612, which may be communicatively coupled to receiver components604, 606 and 608. While FIG. 6 shows two antennas and three receivercomponents, one of ordinary skill in the art will recognize that theembodiments described herein may be applicable to WTRUs having anynumber of antennas and receiver components.

In the example illustrated in FIG. 6 , one of the receiver components604, 606 and 608 may be used at a time based on the target power mode. Afirst receiver component 604 may be used for a WUS reception only andmay consume a first (e.g., very low) amount of power. This may bebecause, for example it may only detect a sequence with a correlator. Asecond receiver component 606 may be used for downlink signal reception,for example with a scheduling restriction (e.g., QPSK modulation only,up to rank-1, and up to 100 PRBs). The second receiver component 606 mayconsume a second amount of power (e.g., low power/energy). A third orNth receiver component 608 may be used for a downlink signal, forexample without a scheduling restriction. The third or Nth receivercomponent 608 may consume a third or Nth power/energy (e.g., a highestpower/energy among the receiver components).

The number of receiver components may be based on WTRU capability. AWTRU may report the number of receiver components supported as a WTRUcapability. One or more sets of receiver components may be supported,and a WTRU may indicate which set it supports. An example of sets mayinclude: a first set (Set-1), which may include a single receivercomponent and may, for example, support a normal power mode only; asecond set (Set-2), which may include two receiver components, whichmay, for example, support WUS reception only or WUS reception and normalpower mode; a third set (Set-), which may include two receivercomponents, which may, for example, support lower power mode and normalpower mode; and a set 4 (Set-4), which may include three receivercomponents, which may, for example, support all power modes.

A WTRU may report a required switching time between receiver components(e.g., a time needed by the WTRU to switch from one receiver componentor set of receiver components to another receiver component or set ofreceiver components). The switching time may depend on the current powermode and target power mode. For example, the switching time may beshorter if the current power mode is a higher power mode than the targetpower mode. Otherwise, the switching time may be longer.

A receiver component or set of receiver components may have a coveragelevel. Two or more receiver components or sets of receiver componentsmay have different coverage levels. A receiver component or set ofreceiver components that may be used for a power mode without schedulingrestriction may support the best coverage. A receiver component or setof receiver components that may be used for only WUS reception maysupport a similar coverage level as the normal power mode. A receivercomponent or set of receiver components that may be used for a powermode with scheduling restriction may support a low or worst coverage,such as lower coverage than the receiver component or set of receivercomponents for normal power mode without scheduling restriction and/orfor WUS reception such as WUS reception only.

In embodiments, a WTRU may use one or more receiver components. The WTRUmay determine a receiver component or set of receiver components to usefor a downlink signal reception. Which receiver component or set ofreceiver components to use for a downlink signal reception may beindicated (e.g., directly or indirectly) to the WTRU. Further, a set ofscheduling restriction parameters (SRPs) may be configured or provided,such as by a gNB. A WTRU may determine which receiver component or setof receiver components to use based on the configured or provided SRPs.A scheduling restriction parameter (SRP) may include one or more of amaximum rank (e.g., for PDSCH and/or PUSCH), a maximum modulation order(e.g., QPSK, 16QAM, 256QAM), a maximum TBS, a candidate transmissionscheme (e.g., single TRP or multi-point TRP), a lowest or minimum codingrate, a maximum number of RBs, a minimum and/or maximum HARQ timeline,and/or a maximum timing advance (TA) value.

One or more search spaces or CORESETs may be configured, and each searchspace may be associated with a set of SRPs. For example, each searchspace ID (SearchSpaceID) may be associated with a set of SRPs. A WTRUmay determine which receiver component, set of receiver components, orpower mode to use based on the search space the WTRU monitors. The DCIfields in the DCI monitored for a search space may be determined basedon the associated set of SRPs. One or more search spaces with differentsets of SRPs may not be monitored at the same time (e.g., in a same slotor a same time window). A WTRU may monitor a subset of search spaceswith a lower or higher power mode and skip monitoring the rest of searchspaces if one or more search spaces overlap in a same time window. Ifone or more search spaces with different sets of SRPs overlap in a timewindow (e.g., in same slot), a WTRU may use a receiver component thatcan receive all search spaces in the time window. The terms search spaceand CORESET may be used interchangeably herein. One or more PDCCHcandidates may be used, and each PDCCH candidate may be associated witha set of SRPs. A WTRU may determine a receiver component, a set ofreceiver components, or a power mode based on the PDCCH candidate inwhich the WTRU receives a DCI.

A WTRU may determine which receiver component, set of components, orpower mode to use based on WTRU RRC connection status (e.g., RRCconnected, RRC idle, and RRC inactive). A first receiver component, setof receiver components or power mode (e.g., low power mode) may be usedwhen a WTRU is in RRC idle or RRC inactive. A second receiver component,set of receiver components, or power mode (e.g., high power mode) may beused when a WTRU is in RRC connected. A WTRU may use a first receivercomponent, set of receiver components or power mode for RRC idle and RRCinactive. The WTRU may use either a first or second receiver component,set of receiver components, or power mode in RRC connected based on adetermined set of SRPs.

A WTRU may determine which receiver component, set of components, orpower mode to use based on a downlink channel type (e.g., PDCCH, PDSCH,SS/PBCH block). Additionally or alternatively, a WTRU may determinewhich receiver component, set of components, or power mode to use (e.g.,in a BWP) based on a bandwidth part identity (e.g., BWP-id of an activeBWP).

A set of SRPs may be configured for each BWP, and a WTRU may determine areceiver component, set of components, or a power mode based on theassociated set of SRPs in the active BWP. A first BWP may be associatedwith a subset of modulation orders (e.g., up to QPSK), and a second BWPmay be associated with a second subset or a full set of modulationorders (e.g., up to 64QAM or 256QAM). Based on the set of modulationorders associated with the BWP, a WTRU may determine the receivercomponent, set of receiver components or the power mode, for example touse when operating (e.g., receiving) in the BWP. The associated set ofmodulation orders (or a maximum modulation order) may be configured ineach BWP configuration.

A CQI table for a CSI reporting may be determined based on the BWP (orBWP-id of an active BWP) and/or the associated set of modulation orders(or a maximum modulation order). The number of entries for MCSindication for a PDSCH scheduling may be determined based on the BWP (orBWP-id of an active BWP) and/or the associated set of modulation orders(or a maximum modulation order). The number of MCS bits in a DCI for aPDSCH scheduling may be determined based on the BWP-ID of the activeBWP. The maximum modulation order may be limited for only downlink oruplink.

A first BWP switching time or gap may be used when the active BWP isswitched between BWPs with the same set of SRPs, and a second BWPswitching time (or gap) may be used when the active BWP is switchedbetween BWPs with a different set of SRPs. A longer switching time (orgap) may be required or used when a receiver component, set of receivercomponents, or power mode is different between BWPs.

A WTRU may determine which receiver component, set of components, orpower mode to use based on one or more of a carrier index (e.g., servingcell ID), a frequency range (e.g., frequency range 1 or frequency range2), a traffic type (e.g., eMBB, mMTC, or URLLC), and/or a QoS type(e.g., latency level, reliability level, required throughput level).

A WTRU may determine which receiver component, set of components, orpower mode to use based on a coverage level. A receiver component, setof receiver components, or power mode may be determined based on thePDCCH aggregation level in which a WTRU received a DCI. A receivercomponent, set of receiver components, or power mode may be determinedbased on one or more downlink measurements (e.g., CQI, SINR, L1-RSRP,RSRP, or RSRQ). A WTRU may monitor a DCI which may be associated withthe determined receiver component, set of receiver components, or powermode.

FIG. 7 is a system diagram 700 showing an example usage of a low powermode receiver in different coverage scenarios. When a WTRU is atcell-edge, such as WTRUs 710 and 712, the WTRU may not be able toreceive a modulation order higher than QPSK, for example due to poorchannel conditions. If a WTRU uses, or a gNB allows a WTRU to use, areceiver component that supports up to QPSK modulation order only, theWTRU may be able to save battery. The receiver component may consumeless power during PDCCH and PDSCH receptions as compared with a receivercomponent supporting a higher modulation order. The WTRU 708, which isnot at cell edge, may operate in a different, higher power mode thatsupports up to 256 QAM.

A WTRU may receive a configuration or indication, such as from a gNB, touse a receiver component, a set of receiver components or a power modethat may support a limited maximum modulation order and/or one or moreother scheduling restrictions. Alternatively, the WTRU may receive aconfiguration or indication of a maximum modulation order that may bescheduled or used and/or one or more other scheduling restrictions. TheWTRU may assume that a modulation order to be scheduled for a downlinkchannel, such as PDCCH or PDSCH, may not be higher than the limitedmaximum modulation order (e.g., QPSK). A maximum transmission rank maybe determined based on the maximum modulation order used for thedetermined receiver component. A maximum transmission bandwidth may bedetermined based on the maximum modulation used for the determinedreceiver component.

A gNB may switch from a low power mode (e.g., up to QPSK) to a highpower mode or vice versa with a dynamic indication (e.g., implicit bysearch space activation or explicit by DCI indication) with a switchingtime. A switching time, such as receiver component switching time, maybe provided and/or used when a maximum modulation order for a downlinkscheduling is increased or decreased. The switching time may be the sameas the switching time for BWP switching. A WTRU may skip monitoringPDCCH during the switching time.

In some embodiments, some radio performance aspects, such as describedabove, may be configured and/or activated independently. For example, afirst type of radio performance state may be defined for RF aspectsincluding, for example, a reference sensitivity level and a number of RFchains, a second type of radio performance state may be configured forbaseband aspects including, for example, a maximum transport block size,and a third type of radio performance state may be defined for RRMaspects. In another example, a first type of radio performance state maybe defined for PDCCH decoding aspects, and a second type of radioperformance state may be defined for PDSCH decoding aspects.

In embodiments, a radio performance state may be configured (e.g. byRRC) by configuring a set of values for at least one applicable aspect.For example, the RRC configuration may include a list of radioperformance states, each including a maximum transport block size,maximum rank, receiver sensitivity values and other information elementsfor applicable aspects. Further, an identity parameter may be configuredfor each radio performance state. The identity parameters may beassigned such that, for example, a higher value may correspond to higherrequirements.

In embodiments, a default radio performance state may be defined. Suchradio performance state may correspond to the set of capabilities of theWTRU provided to higher layers (e.g., maximum performance orcapability). Such default radio performance may not require additionalconfiguration by RRC. Alternatively, a default radio performance statemay correspond to a power-efficient state.

A set of applicable radio performance states may be added to theconfiguration of an applicable aspect. For example, the configuration ofa TCI state may include at least one additional information elementindicating one or more radio performance states for which this TCI statemay be active. This indication could be provided an information elementthat indicates the maximum identity parameter of applicable radioperformance states. In case only two radio performance states aredefined, the information element may be a Boolean value indicatingwhether the TCI state can be activated in the radio performance statecorresponding to a power-efficient state.

Additional information elements may be defined for the configuration ofcertain aspects when in a specific radio performance state. For example,an information element configuring the CSI report configuration when inthe non-default (power-efficient) radio performance state may be used.This may be particularly useful when a large number of parameters areaffected and only 2 performance states (e.g. a default one and apower-efficient one) are defined.

A WTRU may determine the applicable radio performance state based on atleast one of a number of different methods. In some embodiments, theradio performance state may be indicated explicitly by physical layer,MAC or RRC signaling. For example, the WTRU may receive a MAC controlelement indicating a radio performance state or the value for anapplicable aspect. The WTRU may activate the necessary components suchthat it is prepared to operate using the indicated state no later than apre-defined number of slots or symbols (or ms) following transmission ofHARQ acknowledging reception of the corresponding transport block.

For example, in some embodiments, a minimum cross-slot scheduling delay(minimum k0 or minimum k2) may be indicated by a DCI field, such as atime domain resource allocation (TDRA) field. For example, a minimum k0or k2 value may be configured for each codepoint of this field, inaddition to existing parameters, such as k0, mapping type, startingsymbol and length. In case the value of minimum k0 (or k2) indicated bythe field is different than the one currently used by the WTRU, the WTRUmay modify the minimum k0 (or k2) value accordingly. In addition, theWTRU may determine that no PDSCH (or PUSCH) is received or transmitted.This may be applicable only if the indicated minimum value of k0 (or k2)is lower than the current value. The WTRU may determine that the changeof minimum k0 (or k2) is valid on a condition that at least one otherfield of the DCI is set to a pre-defined value, to improve robustness.For example, a frequency-domain resource assignment field may have to beset to a pre-defined value. The WTRU may acknowledge reception of thesignaling by transmitting HARQ-ACK for the corresponding DCI, forexample over a resource indicated by a PUCCH resource indicator.

In some embodiments, the radio performance state may implicitly beswitched or activated when the WTRU receives an activation command foran associated aspect. For example, a TCI state may be configured to beapplicable to a non-default radio performance state, such as onecorresponding to a higher reference sensitivity or a lower number of RFchains. Upon reception of a MAC CE indicating activation of this TCIstate for PDCCH reception, the WTRU may operate according to thecorresponding non-default radio performance state.

In some embodiments, a radio performance state may be determined basedon at least one WTRU measurement, such as RRM measurement, or CSImeasurement, such as L1-RSRP. For example, a WTRU may activate a defaultradio performance state if the RSRP of its serving cell is lower than athreshold. Such threshold may be signaled by MAC or RRC. Conversely, theWTRU may activate a non-default radio performance state if the RSRP ofits serving cell is higher than a threshold. The WTRU may signal suchswitching of the radio performance state using MAC or RRC signaling.

In some embodiments, a WTRU may switch to a radio performance state,such as a radio performance state allowing for maximum performance,after decoding a PDCCH containing a DL assignment or UL grant for thisWTRU. Additionally or alternatively, in some embodiments, a WTRU may beconfigured with a radio performance state timer of a certain duration.The WTRU may start or restart the radio performance timer when decodinga PDCCH containing a DL assignment or UL grant for this WTRU. Uponexpiry of the timer, the WTRU may switch to a power-efficient radioperformance state.

In some embodiments, a radio performance state may be determined basedon whether at least one DRX timer is running or based on reception of aDRX MAC CE. For example, a WTRU may switch to a default radioperformance state when an inactivity timer starts and switch to anon-default radio performance state when an inactivity timer, a UL or DLretransmission timer, and a UL and DL HARQ RTT timer have expired. Inanother example, a WTRU may switch to a non-default radio performancestate after reception of a DRX command MAC CE or of a long DRX commandMAC CE.

In some embodiments, a radio performance state may be configured to beassociated with a BWP. Upon switching to a new BWP, the WTRU may alsoswitch to the associated radio performance state. For example, apower-efficient radio performance state may be configured to beassociated with a bandwidth part with a relatively narrow bandwidth, anda radio performance state allowing for maximum performance may beconfigured to be associated with a bandwidth part with a relatively widebandwidth.

In some embodiments, a radio performance state may be associated with aconfigured grant or assignment. The WTRU may switch to this radioperformance state upon transmission or reception of the configured grantor assignment.

FIG. 8 is a diagram 800 of an example of switching between two radioperformance states. In the example illustrated in FIG. 8 , a WTRU mayswitch between two radio performance states, a first radio performancestate requiring the use of four Rx chains and a second radio performancestate requiring the use of only two Rx chains. In the exampleillustrated in FIG. 8 , a WTRU may be triggered to switch to the firstradio performance state by WTRU scheduling (e.g., reception of DLassignment or UL grant). The WTRU may be triggered to switch to thesecond radio performance state by expiration of a timer. For example, in(a), the WTRU may disable 4 Rx, use only 2Rx and attempt to detect avalid PDCCH. In (b), the WTRU may be scheduled, may start a timer, andmay enable or re-enable 4 Rx processing. When the timer expires, theWTRU may stop monitoring. In (c), the WTRU reverts to 2 Rx and attemptsto detect a valid PDCCH.

In some embodiments, a radio performance state may be determined (e.g.,implicitly) based on scheduling information or a property of the decodedPDCCH. This approach may have the benefit of avoiding the need foradditional DCI formats to switch between states. For example, thescheduling information may include timing information, such as thenumber of slots (e.g., k0 or k2) between PDCCH and PDSCH (or PUSCH) or aduration of PDSCH or PUSCH. For example, the WTRU in a first state mayswitch to a second state if the indicated number of slots k0 is lowerthan a first configured threshold or corresponds to a configured valueor codepoint. Such first threshold may correspond to a minimum numberslots k0min configured for the first state. The WTRU in a second statemay switch to a first state if the indicated number of slots k0 ishigher than a second configured threshold or if the indicated number ofslots k0 corresponds to a certain value or codepoint.

As part of the performance state behavior, for example, a WTRU that hasbeen provided with a k0min (or k2min) and that receives a datascheduling DCI containing or indicating a k0<k0min (or a k2<k2min) mayset the new value of k0min (or k2min) to the received k0 (or k2), or itmay set the value of k0min (or k2min) to a default value such as zeroslots.

There may be a time gap between when the scheduling DCI, implicitlyindicating a new value for k0min (k2min), is received and when thisinformation is available to the WTRU. This delay may be due to variousreceive operations, such as decoding and demodulation. In embodiments, aWTRU may not be buffering any potential PDSCH during the time gapfollowing the PDCCH, and the data in the PDSCH may be lost. In someembodiments, instead of feeding back a NACK for the lost data, the WTRUmay be expected not to send any acknowledgment feedback even if a PUCCHresource is provided in the DCI. In other embodiments, the DCI mayindicate a non-transmission of ACK/NACK, such as by setting the PUCCHresource field (or another predetermined field) to a known value. Thesemethods may in general be applicable when a WTRU performance state isimplicitly switched to another performance state, and a temporary lossof data occurs during the switch.

The scheduling information may also or alternatively include timinginformation, such as the number of slots (denoted as X) between a grant(DL or UL grant) triggering an aperiodic reference signal (e.g., CSI-RSor SRS) and the reception and/or transmission of the aperiodic referencesignal. For example, a WTRU in a first state may switch to a secondstate if the indicated number of slots is lower than a first configuredthreshold or corresponds to a configured value or codepoint. A WTRU in asecond state may switch to a first state if the indicated number ofslots is higher than a second configured threshold or corresponds to aconfigured value or codepoint. As part of the performance statebehavior, a WTRU that has been provided with an Xmin and that receives adata scheduling DCI containing X<Xmin may set the new value of Xmin tothe received X. Alternatively, it may set the value of Xmin to a defaultvalue such as zero slots. This may apply similarly to other possibleparameters, such as SRS triggering offset.

The scheduling information may also or alternatively include frequencyallocation, such as the number of RBs, a set of RBs, or a bandwidthpart. For example, a WTRU in a first state may switch to a second stateif the indicated number of RBs is higher than a configured threshold orif the indicated set of RBs includes RBs outside of a configured subsetof RBs for the first state. Additionally or alternatively, thescheduling information may include information regarding whether theresources of the PDSCH or PUSCH in time or frequency overlap with theresources of a configured assignment or grant or the resources indicatedby another grant or assignment. Additionally or alternatively, thescheduling information may include a BWP indication. For example, a WTRUmay switch to a radio performance state configured for the indicatedbandwidth part if different from the active bandwidth part.

In embodiments, the scheduling information may additionally oralternatively include an MCS or MCS table. For example, the WTRU in afirst state may switch to a second state if the indicated MCS is above aconfigured MCS threshold or if the indicated MCS table is not part of aset of possible MCS tables configured for the first state. Additionallyor alternatively, the scheduling information may include a number oflayers (rank). For example, the WTRU in a first state may switch to asecond state if the indicated number of layers is above a configuredthreshold. Additionally or alternatively, the scheduling information mayinclude a TBS. For example, a WTRU in a first state may switch to asecond if the transport block size determined from the DCI is above aconfigured threshold.

In embodiments, the scheduling information may additionally oralternatively include PDSCH-to-HARQ feedback timing. For example, a WTRUin a first state may switch to a second state if the indicatedPDSCH-to-HARQ feedback latency is lower than a threshold. Such thresholdmay correspond to a minimum value of k1 configured for the first state.Additionally or alternatively, the scheduling information may include atransmission configuration indication (TCI). For example, the WTRU in afirst state may switch to a second state if the indicated TCI is notpart of a set of possible TCIs configured for the first state.Additionally or alternatively, the scheduling information may includeinformation regarding scheduling on supplementary uplink (SUL) or normalUL (NUL). For example, a WTRU in a first state may switch to a secondstate if PUSCH is scheduled on SUL. For example, the second state maycorrespond to a radio performance state with a lower referencesensitivity level or larger number of antennas.

In embodiments, the scheduling information may additionally oralternatively include an indication of a transmission profile that mayindicate a priority associated with a transmission, such as forprioritizing between eMBB and URLLC services. For example, a WTRU in afirst state may switch to a second state if an indicated transmissionprofile is not part of a set of possible transmission profilesconfigured for the first state. Additionally or alternatively, thescheduling information may include information regarding a logicalchannel for which data is included in a transport block. For example, aWTRU in a first state may switch to a second state if the transportblock includes data from a logical channel that is not part of a set ofpossible logical channels configured for the first state. Suchconfiguration may be implicit from logical channel prioritization (LCP)restrictions configured for the logical channel. For example, theconfiguration may implicitly include any logical channel subject to amaximum PUSCH duration restriction where the duration may be lower thana threshold or a logical channel subject to a cell restriction, or alogical channel mapped to a bearer for which duplication is configuredor activated.

In some embodiments, the scheduling information may additionally oralternatively include a PDSCH mapping type. For example, a WTRU in afirst state may switch to a second state if the indicated PDSCH mappingtype is not part of a subset of mapping types configured for the firststate. Additionally or alternatively, the scheduling information mayinclude a radio network temporary identifier (RNTI) used to decodePDCCH. For example, the WTRU in a first state may switch to a secondstate if the indicated RNTI is not part of a subset of RNTIs configuredfor the first state.

In embodiments, a PDCCH-based WUS may be transmitted to a WTRU beforethe DRX ON duration to wake the WTRU up so that it can start monitoringthe PDCCH during the ON duration. The search spaces, CORESETs, andmonitoring periodicities to monitor during the ON duration may beindicated by the RNTI of the WUS. For example, for a first RNTI, a WTRUmay monitor a first set of search spaces, and for a second RNTI, theWTRU may monitor a second set of search spaces. The association betweenan RNTI and associated search spaces may be configured by the gNB.

In other embodiments, CRC bits that are not scrambled with an RNTI maybe scrambled with an R-ID, and the R-ID may be associated with, forexample, a set of search spaces, CORESETs or monitoring periodicities tomonitor during the ON duration. For example, when a WTRU detects a firstR-ID, it may be expected to monitor the associated search spaces. Theassociation between an R-ID and associated search spaces may beconfigured by the gNB. In other embodiments, the R-ID may be the exactID of the search space to be monitored during the ON duration, or it maybe derived from the associated search space with a known relationship.

In embodiments, the scheduling information may additionally oralternatively include a DCI format. For example, a WTRU in a first statemay switch to a second state upon reception of a pre-emption indication(Format 2_1) or of a TPC command (Format 2_2). Additionally oralternatively, the scheduling information may include a property of thedecoded PDCCH, such as a CORESET, a search space, or timing. Forexample, a WTRU in a first state may switch to a second state uponreception of a DCI in a certain configured search space or depending onwhether the search space is a common or dedicated search space.Additionally or alternatively, the scheduling information may be basedon successful decoding of PDCCH whereby the PDCCH schedules a specifictype of transmission. For example, a WTRU may monitor and detect thePDCCH in a first power state and may switch to a second power state ifit is scheduled for a semi-persistent data transmission. For example,the WTRU may use a lower number of RF chains to monitor the PDCCH, and,when it receives and decodes a scheduling PDCCH, it may switch to ahigher number of RF chains if it is scheduled with semi-persistent data.In embodiments, the scheduling information may additionally oralternatively include a number of assignments, grants and/or DCIsreceived within a time period. For example, a WTRU in a first state mayswitch to a second state if such number exceed a configured thresholdwithin a configured time period applicable to the second state.

Similar to the example illustrated in FIG. 8 , for any of the abovepossible triggers based on scheduling, a timer may be started orrestarted when a condition that would lead to determining to use thesecond state is met. Upon timer expiry, the WTRU may switch back to thefirst state.

As an alternative to the embodiment illustrated in FIG. 8 , in someembodiments, one or more DRX cycles and/or configurations may beconfigured and used by a WTRU. Each DRX cycle or configuration may beassociated with a power mode. As mentioned above, a power mode may bepredetermined, configured, defined, and/or used by a gNB and/or WTRU. Apower mode may have one or more attributes, such as power, energy budgetand/or transmit RF chains to use, activate or deactivate. In someembodiments, a power mode may be activated or deactivated based oninformation provided by a WTRU, which may include, for example, acoverage level, channel state information, battery level and/or WTRUcapability (e.g., to support a number of RF chains or turn on/off one ormore RF chains). FIGS. 9, 10 and 11 and the corresponding descriptionprovide examples of different methods of using DRX cycles to implementvarious power modes.

FIG. 9 is a signal diagram 900 of an example of multiple DRXconfigurations based on power mode. In the example illustrated in FIG. 9, two DRX cycles 902 and 904 are configured. The second DRX cycle 904may be longer than the first DRX cycle 902. The first DRX cycle 902 maybe associated with a lower power or power savings mode, and the secondDRX cycle 904 may be associated with a high power or normal power mode.During the ON duration 906 of the first DRX cycle, the WTRU may operatein the lower power mode. For example, the WTRU may turn on only part ofits circuitry (e.g., a subset of the RF chains), or it may turn off ornot use at least some of its circuitry. During the ON duration 908 a,908 b, the WTRU may operate in a normal power mode. For example, it mayturn on and/or use all of its RF chains or a larger subset of the RFchains than for the first DRX cycle 902. As shown in FIG. 9 , since thesecond DRX cycle 904 is longer than the first DRX cycle 902, the secondDRX cycle 904 may include more than one ON duration 908 a, 908 b.

When one or more DRX configurations are used, at least one DRX parametermay be different for each DRX configuration. Use of a DRX cycle maycorrespond to monitoring or not monitoring the PDCCH based on a DRXcycle. For example, use of a DRX cycle may correspond to monitoring ornot monitoring the PDCCH based on at least one parameter, time,duration, timer, or aspect of a DRX cycle or configuration such as an ONduration, an ON duration timer, an active time, and OFF duration, an OFFduration timer, and a retransmission.

A WTRU may use one DRX configuration (or DRX cycle) at a time.Alternatively, a WTRU may use one or more DRX configurations (or DRXcycles) at the same time. Each DRX configuration may be associated witha power mode. For example, high power mode may be associated with afirst Rx configuration (e.g., a larger # of RF chains or a larger # ofactivated or used RF chains), and a low or lower power mode may beassociated with a second Rx configuration (e.g., a smaller # of RFchains or a smaller # of activated or used RF chains).

A PDCCH transmitted by a gNB and/or received by a WTRU may be associatedwith a power mode or may carry associated power mode information. Thepower mode information may indicate the power mode.

A PDCCH that may be associated with a power mode may be monitored orreceived during an ON duration of a corresponding DRX cycle that may beassociated with the power mode.

One or more parameters or aspects of a PDDCH channel or of PDCCHmonitoring may be based on the power mode in use when the PDCCH ismonitored. A WTRU may determine and/or use a parameter or aspect of aPDCCH channel or of PDCCH monitoring based on the power mode being usedby the WTRU when the WTRU monitors the PDCCH. A parameter or aspect maybe at least one of an aggregation level, a set of aggregation levels,and/or a REG-bundle size.

For example, one or more higher levels of aggregation may be neededand/or used for monitoring the PDCCH for a low power or power savingmode, for example due to coverage loss when fewer RF chains are used. Inanother example, a larger REG-bundle size may be needed and/or used formonitoring the PDCCH for a low power or power saving mode.

In embodiments, a first set of aggregation levels may be used to monitora PDCCH in an ON duration or active time associated with a first DRXcycle. A second set of aggregation levels may be used to monitor a PDCCHin an ON duration or active time associated with a second DRX cycle. Inan example, the first set of aggregation levels may include smalleraggregation levels, and the second set of aggregation levels may includelarger aggregation levels. In another example, the second set ofaggregation levels may include at least one aggregation level that islarger than the aggregation levels (e.g., all the aggregation levels) inthe first set of aggregation levels. In embodiments, a first REG-bundlesize may be used to monitor a PDCCH in ON durations associated with ahigh power mode, and a second REG-bundle size may be used to monitor aPDCCH in ON durations associated with a low power mode.

When a WTRU receives a PDCCH while in an ON duration or active time, theWTRU may operate in a power mode, for example to receive data in a PDSCHthat may be scheduled or granted by the PDCCH. For example, if a PDCCHis detected during an ON duration or active time of a certain DRX cycle,then the WTRU may stay in the certain power mode while receiving anassociated PDSCH and/or user data. After a PDCCH is detected during anON duration or active time, the WTRU may start a timer and may monitoror continue monitoring the PDCCH, for example until the timer expires.During this monitoring, the power mode associated with the detectedPDCCH, the ON duration, or the active time may be used.

One or more parameters or aspects of a PDSCH channel or a PDSCHtransmission or reception may be based on a power mode, for example whenthe associated PDCCH is monitored. A WTRU may determine and/or use aparameter or aspect of a PDSCH channel or of a PDSCH transmission orreception based on the power mode being used by the WTRU, for examplewhen the WTRU monitors the associated PDCCH. A parameter or aspect maybe at least one of a rank, a maximum rank, a DM-RS parameter such as aDM-RS density, an MCS level, and/or a maximum MCS level.

A maximum rank for a PDSCH reception may be determined or limited by thepower mode associated with the PDSCH or associated with the PDCCH thatscheduled the PDSCH. The power mode associated with the PDCCH may be thepower mode associated with the DRX cycle, the ON duration and/or theactive time during which the PDCCH was detected. A rank may beinterchangeably used with a number of layers, a number of data streams,a number of a spatial layers, and a number of data symbolssimultaneously transmitted at the same time/frequency. A first maximumrank (e.g., 4) may be used when a WTRU monitors a PDCCH or receives aDCI in an ON duration or active time associated with a first power mode,and a second maximum rank (e.g., 1) may be used when a WTRU monitors aPDCCH in an ON duration or active time associated with a second powermode. The nth maximum rank may be used for reception of a PDSCHscheduled by the PDCCH in the ON duration or active time associated withthe nth power mode. A lower maximum rank may be used for a lower powermode. For example a lower maximum rank may be used for a power savingsmode than a normal mode.

A DM-RS density for a PDSCH reception may be determined based on thepower mode associated with the PDSCH. A first DM-RS density of or for aPDSCH may be used when a WTRU monitors one or more PDCCHs or receives aDCI for the PDSCH in a DRX cycle, an ON duration or an active timeassociated with a first power mode. A second DM-RS density of or for aPDSCH may be used when a WTRU monitors one or more PDCCHs or receives aDCI for the PDSCH in a DRX cycle, an ON duration, or an active timeassociated with a second power mode. A DM-RS density of or for a PDSCHmay be based on or correspond to a number of DM-RS symbols used within aslot. For example, a first DM-RS density may use a first number of DM-RSsymbols (e.g., 4 DM-RS symbols) in a slot for a PDSCH, and a secondDM-RS density may use a second number of DM-RS symbols (e.g., 2 DM-RSsymbols) in a slot for a PDSCH.

A maximum MCS level may be determined based on the power mode associatedwith the PDSCH. A first maximum MCS level (e.g., 256QAM) may be usedwhen a WTRU monitors one or more PDCCHs or receives a DCI for the PDSCHin a DRX cycle, an ON duration, or an active time associated with afirst power mode. A second maximum MCS level (e.g., QPSK) may be usedwhen a WTRU monitors one or more PDCCHs or receives a DCI for the PDSCHin a DRX cycle, an ON duration, or an active time associated with asecond power mode.

A low power mode may be a power savings mode. A high power mode may be anormal or non-power saving mode. active time may be substituted for ONduration in the embodiments and examples described herein and still beconsistent with this disclosure. An ON duration or an active time may beassociated with a DRX cycle and/or a power mode.

Herein, ON duration or active time may be replaced by a duration forPDCCH monitoring, a PDCCH monitoring occasion, and/or a search space. ONduration or active time may include one or more PDCCH monitoringoccasions. ON duration and/or active time may include one or more searchspaces, for example for monitoring the PDCCH. A WTRU may monitor a PDCCHat or during a PDCCH monitoring occasion. PDCCH occasion and PDCCHmonitoring occasion may be used interchangeably herein.

FIG. 10 is a signal diagram 1000 of an example of power mode switchingbetween ON durations in different DRX cycles. In the example illustratedin FIG. 10 , a WTRU may monitor the PDCCH in an ON duration 1002 a of aDRX cycle or in a PDCCH monitoring occasion using an associated powermode. When a PDCCH is detected 1004 during the ON duration 1002 a(1004), the WTRU may operate or continue operating in the same powermode (1006), which may include, for example, at least one of monitoringthe PDCCH, receiving the PDSCH, and transmitting the PUSCH. The WTRU mayreceive an indication to the change the power mode. The indication maybe received in the current ON duration and/or before the next ONduration 1002 b. The message may be transmitted in a DCI in the PDCCH oras a MAC CE or other format. The WTRU may switch the power mode (1008)based on the received indication. The WTRU may make or apply the switchat the start of an ON duration, such as the next ON duration 1002 b orat k (or at least k) PDCCH monitoring occasions after the switchindication is received. The WTRU may then proceed with data reception(1110) during the ON duration 1002 b.

In embodiments, a WTRU may determine a receiver component, a set ofreceiver components or a power mode based on a timer. For example, aWTRU may use a first receiver component, set of receiver components orpower mode to monitor the PDCCH in an ON duration or active time when atimer is running. When the timer expires, the WTRU may switch to asecond or fall-back receiver component, set of receiver components orpower mode. The second or fall-back receiver component, set of receivercomponents, or power mode may have better coverage than the firstreceiver component, set of receiver components or power mode. If thefirst receiver component, set of receiver components, or power mode isalready a fall-back receiver component, set of receiver component orpower mode, the inactivity timer may stop or reset.

A first receiver component, set of receiver components or power mode mayhave a first number of RF chains active. A fall-back receiver component,set of receiver components or power mode may have a second number of RFchains active where the first number may be smaller than the secondnumber. The second number may be a large number or the largest numberthat may be supported by the WTRU based on WTRU capability. Thefall-back receiver component, set of receiver components or power modemay support a maximum modulation order that may be higher than thatsupported by the first receiver component, set of receiver components orpower mode. The fall-back receiver component, set of receiver componentsor power mode may support a highest maximum modulation order that theWTRU may support based on WTRU capability.

In embodiments, a WUS may be used with DRX to save power. As an example,a WUS may precede an ON duration of a DRX cycle. A WTRU may monitor oneor more PDCCHs during the ON duration or active time, for example in oneor more PDCCH occasions or monitoring occasions, when a WUS is detected.

In embodiments, a WTRU may determine a receiver component, set ofreceiver components or power mode for monitoring the PDCCH in an ONduration or active time based on an associated WUS. The associated WUSmay indicate which receiver component, set of receiver components orpower mode to use. For example, one or more WUSs may be used, and, if aWTRU receives a first WUS, the WTRU may use or turn-on a first receivercomponent, set of receiver components or power mode. If the WTRUreceives a second WUS, the WTRU may use or turn-on a second receivercomponent, set of receiver components or power mode.

One or more WUSs may be based on preambles, and a WTRU may blindlydetect the preambles. If a first preamble is detected, a WTRU may use afirst receiver component, set of receiver components or power mode, andthe WTRU may use a second receiver component, set of receiver componentsor power mode if a second preamble is detected

FIG. 11 is a signal diagram 1100 of an example of a WUS determining apower mode of associated PDCCH monitoring occasions and a set ofaggregation levels for the PDCCH monitoring. In the example illustratedin FIG. 11 , the WUS may indicate the number of RF chains to turn on orthe power mode to use. For example, the WUS 1102 may be used to wake upthe WTRU in a first power mode while a second WUS 1104 may be used towake up the WTRU in a second power mode.

A set of aggregation levels to be monitored in a certain search spacemay be determined based on the power mode indicated by the WUS. Forexample, a search space may be configured with one or more sets ofaggregation levels. Each set of aggregation levels may be associatedwith a power mode. Based on the indicated power mode, a WTRU maydetermine the set of aggregation levels for PDCCH monitoring in thesearch space. For a first power mode, larger aggregation levels may beused, for example larger than for a second power mode. Larger levelsmay, for example, be used for a low power mode since the receivercapability may be limited, for example, due to use of less active RFchains. For a second power mode, smaller aggregation levels (e.g., asmaller maximum aggregation level) may be used, for example, since thefull receiver capability may be supported.

In other embodiments, a WUS may determine a first receiver component,set of receiver components or power mode for PDCCH monitoring, forexample in the associated ON duration, active time or one or moreassociated PDCCH monitoring occasions or PDCCH occasions. A WTRU maydetect or receive a PDCCH, for example in the associated ON duration,active time, or PDCCH monitoring occasions. The PDCCH may indicate asecond receiver component, set of receiver components or power mode touse for the associated PDSCH reception.

The first receiver component, set of receiver components or power modeand the second receiver component, set of receiver components or powermode may be the same, for example when the first receiver component, setof receiver components or power mode is a high or normal power mode. Inembodiments, a WUS may include a sequence or a combination of two ormore sequences. If two or more sequences are used, at least one of thefollowing may be used to generate the WUS: scrambling the sequences,time division multiplexing of the sequences, and frequency divisionmultiplexing of the sequences. At least one of the constituent sequencesof the WUS may indicate the power mode. For example, if two sequencesare scrambled to generate a WUS, one of the sequences may indicate thepower mode.

In some embodiments, a radio performance state may be determinedimplicitly when a WTRU receives downlink control information indicatinga DL assignment or UL grant that cannot be followed by the WTRU based onthe current radio performance state or capabilities. For example, uponreception of a DCI indicating a change of active bandwidth part (e.g.,indicated BWP index different from the active BWP) if the DCI indicatesa PDSCH or PUSCH that starts before the end of an allowed switching gap,a WTRU may switch to a configured radio performance state. For anotherexample, a radio performance state may be implicitly determined uponreception of a DCI with a carrier indicator field that does notcorrespond to any configured carrier. In this case, the value of thefield may map to an index of the radio performance state. For anotherexample, a radio performance state may be implicitly determined uponreception of an assignment or grant with a codepoint corresponding to areserved or invalid value (e.g., for the antenna port field). Foranother example, a radio performance state may be implicitly determinedupon reception of an assignment or grant with invalid HARQ information,such as when receiving a HARQ process index larger than the configurednumber of HARQ processes. For another example, a radio performance statemay be implicitly determined upon reception of an assignment or grantindicating invalid resources.

When the radio performance state is determined based on one of the aboveexamples, the WTRU may switch to a default radio performance stateregardless of the contents of the DCI. Alternatively, the WTRU mayswitch to a radio performance state indicated by the value or values ofat least one field.

In some embodiments, the performance state of a WTRU may contradict theinformation carried in the data scheduling DCI, resulting in a mismatch.Such mismatch may happen, for example, if the WTRU misses signaling thatdetermines the performance state. For example, in some embodiments, aWTRU may be configured to deactivate certain entries of the TDRA table.For example, the entries with k0 (k2) that are below a threshold k0min(k2min) may be deactivated. In this context, deactivation may imply thatthe WTRU shall not expect to be scheduled with the deactivated entries.It may be assumed that the k0min (k2min) is provided to the WTRU via L1,L2, or higher layer signaling. Similarly, a WTRU may be configured todeactivate certain entries of the CSI reporting trigger state list. Forexample, the entries with X (X is the aperiodic CSI-RS triggeringoffset) that are below a threshold Xmin may be deactivated. In thiscontext, deactivation may imply that the WTRU shall not expect to bereceiving the CSI-RS corresponding to the deactivated entries.

If a WTRU, for example, expects to be scheduled with k0 (k2)>0 slots andX>0 slots, then it may enter micro sleep mode as soon as a PDCCH in thecurrent slot is received unless it was scheduled to perform some otheroperation by the PDCCH of a previous slot. A mismatch may occur if aWTRU is configured with k0min but receives a data scheduling DCIindicating a k0 where k0<k0min. Similarly, a mismatch may occur if aWTRU is configured with k2min but receives a data scheduling DCIindicating a k2 where k2<k2min. A mismatch may also occur if a WTRU isconfigured with Xmin but receives a data scheduling DCI indicating an Xwhere X<Xmin.

When a mismatch occurs, in some embodiments, a WTRU may be expected toswitch from the current performance state to the performance stateassociated with the k0/k2/X values indicated in the data scheduling DCI.For example, a WTRU that is configured with k0min=k2min=Xmin=1 slot andoperating in a power saving state may switch to another performancestate (e.g. non-power saving state) if it receives a data scheduling DCIindicating at least one of k0/k2/X to be 0 slots. As part of theperformance state behavior, for example, a WTRU that has been providedwith a k0min/k2min/Xmin and receives a data scheduling DCI containingk0<k0min and/or k2<k2min and/or X<Xmin may set the new value ofk0min/k2min/Xmin to the received k0/k2/X. Alternatively, it may set thevalue of k0min/k2min/X to a default value, such as zero slots.

When a mismatch occurs, in some embodiments, a WTRU may send assistanceinformation to the gNB indicating the occurrence of the mismatch. AMAC-CE may be used to transmit such information.

In another embodiment, a WTRU may be configured with k0min (k2min) butreceive data scheduling DCI indicating a k0 (k2) where k0>k0min(k2>k2min). This may occur as a result of a scheduling decision or amismatch. If each scheduling DCI continuously indicates k0>k0min(k2>k2min) over a certain period of time, the WTRU may send assistanceinformation to the gNB indicating the possible occurrence of a mismatch.The same may also apply for X.

In embodiments, a mismatch may occur when a WTRU in a first performancestate configured with a certain MIMO rank and/or number of Tx/Rx RFchains receives a data scheduling DCI that indicates a contradictingrank and/or number of RF chains. For example, a WTRU may be configuredwith Kmax (Kmax being the maximum rank) and/or Rmax (Rmax being themaximum number of active Tx and/or Rx RF chains) but receives a datascheduling DCI indicating K>Kmax and/or R>Rmax. When such mismatchoccurs, the WTRU may be expected to switch from the current performancestate to a state associated with the information carried in the DCI. TheWTRU may also send assistance information to the gNB indicating theoccurrence of the mismatch. A MAC-CE may be used to transmit suchinformation. In other embodiments, if a WTRU is continuously scheduledwith K (R) that is smaller than Kmin (Rmin) over a certain period oftime, it may send assistance information to the gNB indicating thepossible occurrence of a mismatch.

In general, when the data scheduling DCI has information thatcontradicts the performance state of a WTRU, the WTRU may switch itsperformance state to the state associated with the information containedin the DCI and send an assistance information to the gNB indicating amismatch if a single occurrence of contradiction is sufficient toestablish a mismatch. Alternatively or additionally, the WTRU may sendassistance information to the gNB indicating a possible mismatch if asingle occurrence of contradiction is not sufficient to establish amismatch but such contradiction occurs continuously over a specificperiod of time.

In some embodiments, a WTRU may transmit an acknowledgment ornotification that the radio performance state has been changed, forexample, as a result of applying one of the embodiments described in theabove. The WTRU may transmit the acknowledgment using physical layer,MAC or RRC signaling. For example, an acknowledgment may be transmittedover PUCCH (or as uplink control information (UCI) multiplexed overPUSCH) as a single bit, such as HARQ-ACK, which may be multiplexed withother HARQ-ACK and/or other UCI. In another example, a notification maybe transmitted in a MAC control element or RRC message.

The change of state may be signaled using a transmission to be decodedby more than one WTRU. For example, the change of state may be signaledusing a PDCCH received from a group-common search space and a C-RNTIassigned to a group of WTRUs. Such transmission may be a power savingsignal, examples of which are described above. The WTRU may use at leastone of the following embodiments to determine the PUCCH resource overwhich to transmit the acknowledgment. Such embodiments may also be usedfor scenarios other than power saving signaling where a change of stateis signaled using group signaling.

In some embodiments, the payload of the power saving signal may indicatethe PUCCH resource for every WTRU in the group, such as where the powersaving signal is WTRU group specific. A WTRU may first identify thelocation of the group of bits within the DCI that indicate the PUCCHresource that the WTRU is going to use to transmit the ACK/NACK. Eachset of bits may indicate a row of a table, and the row may containinformation pertaining to the PUCCH resource. The group of bits mayindicate non-transmission of ACK/NACK (e.g., by setting the bits to apredetermined value) and the location of the PUCCH resource. Forexample, assuming 2 bits, 00 may indicate non-transmission of ACK/NACKand 01, 10, and 11 may each indicate a specific PUCCH resource.

The location of the group of bits may be determined by the WTRU using areference to another bit within the DCI payload. As an example, with 3WTRUs in the group, each bit in the first 3 bits may indicate whether towake-up or not for a specific WTRU, and, assuming 2 bits for PUCCHresource indication, the following 2 bits may indicate the PUCCHresource for the 1^(st) WTRU, the following 2 bits may indicate thePUCCH resource for the 2^(nd) WTRU, and so on. The index of the WTRU(i.e. 1^(st), 2^(nd), etc.) may either be configured or derived as afunction of the WTRU ID.

In some embodiments, a WTRU may be configured with a default radioperformance state per BWP. In each on duration, the WTRU may initiallymonitor a default radio performance state of the active BWP or BWPs. Forexample, the WTRU may be configured with a default search space or adefault CORESET per BWP. In each on duration, the WTRU may initiallymonitor the default search space or a default CORESET of the active BWPor BWPs.

Upon receiving a PDCCH during a given ON duration or DCI format, a WTRUmay change a power savings aspect or radio performance state, forexample, without changing its active BWP. For example, upon decoding aPDCCH for the WTRU during a given on duration, the WTRU may increase thenumber of monitored search spaces or CORESETs in the active BWP. Suchincrease may be binary, such as where all search spaces or CORESETs aremonitored, or gradual, such as dependent on an RRC configuration.

Upon the expiry of a timer, such as a DRX inactivity timer, the WTRU maychange a power savings aspect or radio performance state, for example,without changing its active BWP. For example, upon the expiry of the DRXinactivity timer or BWP inactivity timer, the WTRU may reduce the numberof monitored CORESETs or the number of monitored search spaces, forexample, to only the default search space or the default CORSET of theactive BWP or BWPs.

In other embodiments, upon receiving a WUS during a given on duration, aWTRU may change a power savings aspect or radio performance state,without changing its active BWP in some embodiments. For example, uponreceiving a WUS during a given on duration, the WTRU may increase thenumber of monitored search spaces or CORESETs in the active BWP. Suchincrease may be binary, such as where all search spaces or CORESETs aremonitored, or gradual.

A WTRU may further consider the content of PDCCH scheduling informationprior to changing a radio performance state (e.g., number of monitoredsearch spaces or CORESETs). For example, prior to changing the radioperformance state, the WTRU may consider one or more of the size of thescheduled TB, the logical channel or DRB on which data is scheduled, anaspect of QoS of the scheduled data (e.g., service type or latencyinvolved), and provided characteristics of a scheduled UL grant. Inembodiments, a WTRU may consider the size of the UL grant and/or theamount of buffered data. In other embodiments, a WTRU may consider LCPmapping restrictions of the UL grant with respect to the buffered ULdata.

The WTRU may further consider one or more of the above metrics togradually change the radio performance state. For example, the WTRU mayconsider one or more of the metrics above to determine the number ofadditional search spaces to monitor, for example, depending on an RRCconfiguration.

In embodiments, one or more CSI reporting values, ranges, or indexes fora CSI reporting may be determined based on a receiver component, a setof receiver components, or a power mode. Determination may be made by aWTRU.

A CQI table may be determined based on a power mode. For example, afirst CQI table may be used for a first power mode, and a second CQItable may be used for a second power mode. A set of modulation ordersmay be different based on the CQI table. A CQI table for a first powermode may include a subset of modulation orders (e.g., QPSK only), and aCQI table for second power mode may include full set of modulationorders (e.g., QPSK, 16QAM, and 64QAM). The number of entries for a CQItable may be different based on the associated power mode. For example,3-bit CQI table (8 entries) may be used for a first power mode and 4-bitCQI table (16 entries) may be used for a second power mode.

A full set or a subset of CQI entries in a CQI table may be used basedon the power mode. Table 2 shows an example of determining a full set ora subset of CQI entries based on the associated power mode. In theexample, power mode 1 uses CQI entries with QPSK, and power mode 2 usesCQI entries with all modulation orders.

The number of CQI bits for a CQI reporting may be determined based onthe number of CQI entries in the set or subset determined for the powermode. Alternatively, the number of CQI bits for a CQI reporting may beunchanged based on power mode and determined based on the full set ofCQI entries in the CQI table. CQI entry, CQI index, and CQI value may beused interchangeably.

TABLE 2 CQI modu- code rate × effi- Power Mode Power Mode index lation1024 ciency 1 (Low) 2 (High)  0 out of range  1 QPSK 78 0.1523 v v  2QPSK 120 0.2344 v v  3 QPSK 193 0.3770 v v  4 QPSK 308 0.6016 v v  5QPSK 449 0.8770 v v  6 QPSK 602 1.1758 v v  7 16QAM 378 1.4766 v  816QAM 490 1.9141 v  9 16QAM 616 2.4063 v 10 64QAM 466 2.7305 v 11 64QAM567 3.3223 v 12 64QAM 666 3.9023 v 13 64QAM 772 4.5234 v 14 64QAM 8735.1152 v 15 64QAM 948 5.5547 v

A maximum reported rank may be limited based on the power mode. Forexample, a first maximum reported rank (e.g., 4) may be used when afirst power mode is determined for a CSI reporting. A second maximumreported rank (e.g., 1) may be used when a second power mode isdetermined for a CSI reporting. The maximum reported rank, a maximumrank index (RI) value, and a maximum RI may be used interchangeably.

A codebook subset restriction level may be determined based on the powermode. A minimum required CSI computation time for a given CSI reportingsetting or CSI reporting configuration may be different based on thepower mode. A shorter minimum required CSI computation time may be usedfor a high power mode and a longer minimum required CSI computation timemay be used for a low power mode.

In some embodiments, one or more configured CSI reporting settings,resource settings, and/or CSI reporting configuration may be activatedor deactivated based on the power mode used. For example, a CSIreporting setting may be deactivated when one or more conditions aremet. Activation and/or deactivation may be performed by a WTRU. Acondition may be one or more of the determined receiver component or setof components is or corresponds to a low power mode, the number ofantenna ports of the associated NZP-CSI-RS for the CSI reporting islarger than a threshold (e.g., 8), the associated codebook type is TypeII, the number of beams to measure for L1-RSRP is larger than athreshold (e.g., 64), and a CSI reporting is a periodic reporting orsemi-persistent reporting.

In some embodiments, a set of CSI reporting settings, resource settings,and CSI reporting configuration may be configured for per receivercomponent, set of receiver components, or power mode. For example, afirst set of CSI reporting settings, resource settings, and CSIreporting configurations may be configured or used for a first receivercomponent, set of receiver components, or power mode. A second set ofCSI reporting settings, resource settings, and CSI reportingconfiguration may be configured for a second receiver component, set ofreceiver components, or power mode.

A WTRU may report a CSI based on the set of CSI reporting settings,resource settings, and CSI reporting configurations associated with adetermined or current power mode. A WTRU may report a CSI based on theset of CSI reporting settings, resource settings, and CSI reportingconfiguration associated with an indicated power mode. The power modemay be indicated in an aperiodic CSI reporting trigger, or the powermode may be implicitly indicated by the aperiodic reporting requestindex.

In some embodiments, a same set of CSI reporting settings, resourcesettings, and CSI reporting configurations may be configured for some orall supported power modes. A WTRU may be requested to report theconfigured CSI with one or more power modes. For example, a WTRU may berequested to report a CSI based on a power mode. The WTRU may berequested to report a CSI based on the set of power modes supported bythe WTRU. If the indicated power mode for a CSI reporting is differentfrom the current power mode, a measurement gap may be provided or usedfor the CSI measurement. During a measurement gap, a WTRU may or may beallowed to skip monitoring PDCCH.

When a CSI reporting is based on multiple power modes, a delta offset ofa CSI measurement may be used across power modes. For example, areference CQI value may be measured based on a highest CQI value or aCQI value based on the highest power mode within the CQI values formultiple power modes, and delta CQI value for the rest of power modesmay be reported.

In some embodiments, a WTRU may measure and report a CSI based on thedetermined power mode when the measurement resource is available. TheWTRU may indicate the associated power mode for or with each CSI report.The WTRU may indicate the identity of the power mode.

One or more PUCCH resources may be configured, and one of PUCCHresources may be determined based on the associated power mode. A WTRUmay use the determined PUCCH resources, for example, for CSI reporting.

In some embodiments, a CSI reporting setting, resource setting, orconfiguration may include an attribute associated with a receivercomponent, a set of resource components, or a power mode. For example, afirst CSI resource may be configured so that the CSI-RS transmitted inthat resource may be measured with a first number of RF chains. AnotherCSI resource may be configured so that the CSI-RS transmitted in thatresource may be measured with a second number of RF chains.

FIG. 12 is a signal diagram 1200 of an example of aperiodic CSIreporting triggering with associated power mode indication. In theexample illustrated in FIG. 12 , the DCI 1202 includes a power modeindication. The CSI-RS 1206 may be transmitted after an offset time 1204from the DCI activation. The CSI-RS may be associated with a specificpower mode. In embodiments, the DCI may not need to include a power modeindication, such as when a CSI-RS resource is associated with a powermode. The association may be configured by higher layers. A WTRU may beperforming a CSI measurement using the CSI-RS reference signals and theindicated power mode. The WTRU may report the measurement in anassociated CSI report 1210, for example, a reporting offset 1208 afterthe CSI RS 1206.

FIG. 13 is a signal diagram 1300 of an example of periodic CSI-RS andaperiodic CSI reporting. In the example illustrated in FIG. 13 , whenthe CSI-RS is periodic and the CSI reporting is aperiodic, each CSIresource may be associated with a specific power mode. An activationmessage or trigger message 1302 may, for example via DCI or higherlayers, indicate a power mode that may be used by the WTRU to determinea CSI-RS resource for measurement. The WTRU may make the measurement ofthe CSI reference signals 1304 and 1308 using the power mode or modesindicated in the activation of trigger message 1302. In the exampleillustrated in FIG. 13 , the WTRU measures the CSI-RS 1304 using a firstpower mode and measures the CSI-RS 1308 using a second power mode. A DCI1306 may trigger the WTRU to report a CSI corresponding to one or morespecific power modes. A reporting offset 1310 after the DCI 1306, theWTRU may send the CSI report 1312, which may be for one or both powermodes.

FIG. 14 is a signal diagram 1400 of an example of periodic CSI-RS andperiodic CSI reporting. When the CSI-RS is periodic and the CSIreporting is also periodic, a CSI-RS resource may be associated with aspecific power mode. In the example illustrated in FIG. 14 , forexample, the activation message 1402 indicates that the first power modeis associated with the CSI-RS 1406 and the second power mode isassociated with the CSI-RS 1410. When the WTRU receives the activationmessage 1402, the WTRU may activate 1404 and measure the CSI-RS 1406using the first power mode and measure the CSI-RS 1410 using the secondpower mode. The activation message 1402 may request or command the WTRUto report the CSI corresponding to the indicates power modes.Accordingly, after measuring the CSI-RS 1406, the WTRU sends the CSIreport 1408, and after measuring the CSI-RS 1410, the WTRU sends the CSIreport 1412, without any further signaling needed to triggering the CSIreporting.

The measurement the WTRU performs may not be limited to CSI. Forexample, the WTRU may measure RSRP or another quantity. A WTRU may useCSI-RS or some other reference signals to perform measurements. Forexample a WTRU may use SS-PBCH blocks to perform measurements. EachSS/PBCH block may be associated with a specific power mode. A WTRU mayperform a measurement of an SS/PBCH block while operating with theassociated power mode. WTRU measurements may include coverage level.

A power mode may determine the maximum number of data streams a WTRU mayreceive. A maximum or minimum number of RF chains that may be turned onor used or the power mode that may be used may be indicated to a WTRU.The indication may be based on explicit indication or implicitindication as described in detail above. The indication may be carriedin a DCI format in PDCCH, in a MAC CE, or in a configuration messagefrom the higher layers. A WTRU may operate with an indicated number ofRF chains or power mode, for example in response to or based on theindication or based on receiving the indication.

In embodiments, a timer may be used for a power mode determination. TheWTRU may operate in the power mode until the power mode is modified ordeactivated, for example via a subsequent indication or based on a timerexpiry. The subsequent indication may overwrite or supersede a previousindication. The WTRU may operate in the power mode until another powermode activated, for example via a subsequent indication or based on atimer expiry. The subsequent indication may overwrite or supersede aprevious indication.

A timer may be configured, for example by a gNB, and/or used by a WTRU,when a power mode is configured, activated or used. The timer may beused for a subset of power modes. For example, the timer may be used forpower modes other than a normal power mode. The normal power mode may beconsidered as a fallback power mode. When the timer expires, a WTRU mayswitch to the normal power mode.

A timer may be started or restarted by a WTRU when a maximum rank orpower mode is received or determined by the WTRU and/or indicated orconfigured by the gNB. The timer value may be indicated or determinedwhen the maximum rank or power mode is indicated and/or when the timeris started or restarted. The indication may include or identify thetimer value. Alternatively, a timer value may be associated with amaximum rank or power mode. Indication of a maximum rank or power modemay implicitly indicate the timer value based on the association. Whenusing a maximum rank or a power mode, the WTRU may use the timer valueassociated with the maximum rank or power mode.

When the timer expires, the WTRU may stop using the maximum ranklimitation or the power mode that may be associated with the timer. TheWTRU may use a different maximum rank or a power mode that may beconfigured or otherwise known. The WTRU may use a first set of rankswhen the timer is running or not started and a second set of ranks whenthe timer expires or is not running. The maximum rank in the first setof ranks may be lower than the maximum rank in the second set of ranks.When the timer expires, the WTRU may use, resume, or switch to adefault, fallback, predetermined, or other operation mode, for examplethe normal power mode.

FIG. 15 is a signal diagram 1500 of an example maximum rank restrictionwith a timer. In the example illustrated in FIG. 15 , a base station,such as a gNB, provides a message 1502 that includes a maximum rank. Atrigger offset 1504 after the message 1502, the base station may beginusing the maximum rank limitation (1506), and a WTRU may set a timer.When the timer expires (1508), the maximum rank limitation may end(1510).

In other embodiments, a WTRU may receive a first indication or messagecontaining or identifying a first maximum rank or power mode. The WTRUmay operate with the first maximum rank or power mode, for example afterreceiving the first indication or message. The WTRU may receive a secondindication or message containing or identifying a second maximum rank orpower mode. The second indication or message may overwrite or supersedethe first indication or message. The second maximum rank or power modemay overwrite or supersede the first maximum rank or power mode. TheWTRU may operate with the second maximum rank or power mode, for exampleafter receiving the second indication or message.

In other embodiments, a WTRU may receive a DCI in a PDCCH for resourceallocation, and the rank information in the DCI may be higher than themaximum rank that was previously sent, configured or received. When theWTRU receives a rank that is higher than the maximum rank previouslysent, configured or received, the WTRU may assume that the existingmaximum rank limitation has been voided and start or resume a defaultmode. This default mode may, for example, be normal power mode, a modewith all RF chains activated, and/or a mode with the maximum rank set tothe maximum possible allowed by the WTRU capability or WTRU hardware.Limitation and restriction may be used interchangeably herein. Inembodiments, one of the following may be determined based on the maximumrank: a DM-RS configuration and a power level of RS.

A BWP may be determined based on the maximum rank. There may be at leastone BWP configured, and each BWP may be associated with a least one of amaximum rank, a maximum number of RF chains, a power mode and/or anotherparameter relate to WTRU power consumption. When a BWP is activated, aWTRU may assume that one, more or all of the associated parameters arevalid for the duration of transmission and/or reception within the BWP.The assumption may not apply for a parameter that is overwritten orreconfigured, for example by the gNB, for example via DCI, MAC, orhigher layer signaling. When a parameter is overwritten or reconfiguredwith a new value, the WTRU may use the new value.

A CORSET configuration may be determined based on the maximum rank.There may be at least one CORESET configuration, and each configurationmay be associated with at least one of the following parameters: amaximum rank, a maximum number of RF chains, a power mode; and/oranother parameter related to WTRU power consumption. When a CORSET isconfigured, a WTRU may assume that one, more or all of the associatedparameters are valid for the duration of transmission or when monitoringand/or receiving the CORESET. The assumption may not apply for aparameter that is overwritten or reconfigured, such as by the gNB, forexample via DCI, MAC, or higher layer signaling. When a parameter isoverwritten or reconfigured with a new value, the WTRU may use the newvalue.

Within a CORESET, there may be multiple search spaces where the WTRUmonitors the PDCCH. Each search space may be associated with one or moreparameters described herein, such as one or more parameters related toWTRU power consumption. When monitoring a search space or whenmonitoring or receiving a PDCCH in a search space, the WTRU may use oneor more associated parameters that may be related to WTRU powerconsumption.

A WTRU may be configured with one or more levels of power saving. Forexample, a WTRU may be configured with deep sleep mode (e.g., firstpower mode) and/or a partial sleep power saving mode (e.g., second powermode). In the deep sleep power saving mode, one or more entire RF chainsmay be turned off. In the partial sleep mode, certain functions withinone or more RF chains may be shut down. For example, an RF function thatmay need or use a longer warm up time may stay on in the partial sleepmode.

During the C-DRX operation, a WTRU may perform radio link monitoring(RLM) using all of its available receive antennas (N_(RX)) over the DRXON period. A WTRU may rely on radio link measurements to adapt thedimension of the RX RF chain according to the link quality. Herein, RFchain may refer to an actual RF signal chain, or some specific functionsof an actual RF chain or the entire or some part of an antennasubsystem.

In embodiments, a WTRU in the C-DRX mode may be configured with aminimum allowed number of receive antennas (N_(RLM_min)) for radio linkmonitoring where N_(RX)≥N_(RLM_min)≥1. The minimum allowed number ofreceive antennas (N_(RLM_min)) may be defined based on one or morecriteria such as traffic type, reliability or, downlink transmissionrank. In embodiments, if the measured downlink radio link quality isgreater than a threshold (Q_(in_Ant_K)) for a specified period of time(T_(in_Ant)), one or more of the following may apply: a WTRU may reducethe number of active Rx RF functions, chains and/or Rx antennas fromN_(RX) to K, where K≥N_(RLM_min) or a WTRU may change its power modefrom a higher power mode to a lower power mode. In embodiments, thepower mode may consume more power/energy than a lower power mode.

FIG. 16 is a graph 1600 showing an example of the number of Rx RF chainsdecrementing based on RLM measurement. In the example illustrated inFIG. 16 , the number of Rx RF chain is reduced when the RLM measurementexceeds the threshold Q_(in_Ant_K). As illustrated in FIG. 16 , byreducing the number of antennas, the RLM measurement has ceased crossingthe Q_(in_Ant_K) level. However, it still remains above the requiredQ_(out) threshold to stay in-sync.

The Q_(in_Ant_K) threshold may be defined as a relative offset fromQ_(in) or Q_(out), where Q_(in) and Q_(out) are the in-sync andout-of-sync thresholds, respectively. In an example, Q_(in_Ant_K) may bedefined as Q_(in_Ant_K)=Q_(in)+ΔQ, or alternativelyQ_(in_Ant_K)=Q_(out)−ΔQ. A WTRU may expect the relative offset, ΔQ, tobe defined based on one or more criteria, such as traffic type,reliability, or downlink transmission rank. For example, a URLLC WTRUthat deals with high reliability transmissions may select or beconfigured with a larger Q_(in_Ant_K) value than an mMTC WTRU that isexpected to have a longer battery life.

In embodiments, if the measurement downlink radio link quality goesbelow a threshold (Q_(out_Ant_K)) for a specified period of time(T_(out_Ant)), the WTRU may increase the number of active Rx RFfunctions, chains and/or Rx antennas back to the default dimension ofN_(RX).

FIG. 17 is a graph 1700 showing a number of Rx RF chains incrementingbased on RLM measurement. In the example illustrated in FIG. 17 , thenumber of active RF chains is reversed to the default dimension N_(RX)as the RLM measurement indicates a downward change. As shown in FIG. 17, the RLM measurement enhances. In embodiments, T_(out_Ant) may beselected shorter than T_(int_Ant) to accommodate power up time for RFcomponents. In some embodiments, the timers T_(in_Ant) and T_(out_Ant)may be reset with the expiry or start of the T310 timer used for RLMmeasurement.

In embodiments, a WTRU may indicate a change in the number of Rx RFchains used by the WTRU to the gNB. Following the indication, a WTRU mayexpect a change in PDCCH aggregation level. The change in PDCCHaggregation may be definite or indefinite. A WTRU may expect the changein PDCCH aggregation level to be effective in n+k slot, where n and kare the current slot and offset indices, respectively. In embodimentswhere there is a definite change in PDCCH aggregation, a WTRU mayattempt PDCCH decoding using one or two specific larger aggregationlevels. For example, a WTRU may only expect one or two of the highestavailable aggregation levels for its PDCCH decoding. Alternatively, inembodiments where there is an indefinite change in PDCCH, a WTRU mayonly prioritize larger aggregation levels for PDCCH blind decoding.

In other embodiments, a WTRU may indicate the possibility of a change inthe number of Rx RF chains to the gNB. Following the indication, a WTRUmay be provided with an indication to proceed with a change. If the WTRUdoes not receive a change or a confirmation of its suggested change, theWTRU may maintain its current Rx RF configuration.

On a condition that a WTRU is allowed to proceed with the change, it mayalso assume to be receiving further information related to PDCCHdecoding, such as PDCCH aggregation level. For example, a WTRU may beprovided with an indication that there will not be a change inaggregation level. Alternatively, a WTRU may be provided with anindication to use a lager aggregation level for its PDCCH decoding.

In other embodiments, a power mode may be associated with a set of oneor more measurement parameters or requirements. For example, a powermode may be associated with at least one of the following measurementparameters for a particular measurement: a measurement reporting period(e.g., for a periodic measurement), a timer, a counter, a measurementthreshold that may be used to determine when to trigger a measurementreport, an accuracy requirement, a time duration over which an accuracyrequirement may be met, and/or a measurement sampling requirement suchas a minimum number of measurement samples to make over a period oftime, for example to average to determine the measurement value.

A first power mode may be associated with a first measurement parameteror a first set of measurement parameters for a measurement. A secondpower mode may be associated with a second measure measurement parameteror a second set of measurement parameters for the measurement. A WTRUmay use the first measurement parameter or the first set of measurementparameters when operating in the first power mode. The WTRU may use themeasurement parameter or the second set of measurement parameters whenoperating in the second power mode. The first measurement parameter andthe second measurement parameter may be the same parameter with adifferent value, rule or requirement. The first and second sets ofmeasurement parameters may comprise a same set of parameter types whereat least one parameter type in the first set may have a different value,rule or requirement than the same parameter type in the second set.

There may be multiple levels (e.g., level 1, level 2, level 3) of sleepor power savings modes, such as no sleep, full sleep, normal or regularsleep, deep sleep, or partial sleep. A power mode may correspond to alevel of sleep.

A measurement parameter for a second power mode may be relaxed or lessstringent than the measurement parameter for a first power for a certainmeasurement. For example, a time duration over which an accuracyrequirement may be met for a measurement may be longer for a secondpower mode than a first power mode.

One or more measurement parameters for a power mode may be set byspecification. One or more measurement parameters for a power mode maybe configured. One or more measurement parameters for a power mode maybe a function of the power mode. A WTRU may determine a measurementparameter for a measurement based on a power mode that the WTRU may beusing. A WTRU may make and/or report the measurement using or incompliance with the determined power mode.

A measurement may be a least one of CQI, SINR, L1-RSRP, RSRP, RSRQ, orpathloss. A measurement may be of a reference signal or synchronizationsignal, such as CSI-RS, ZP-CSI-RS, NZP CSI-RS, SSS, or DM-RS. Ameasurement may be an SS/PBCH block measurement.

A power mode may be associated with one or more timers, counters,measurement parameters, and/or thresholds that may be related to inand/or out of synchronization determination. A WTRU may use one or moretimers, counters, measurement parameters, and/or thresholds that may berelated to in and/or out of synchronization determination to make an inand/or out of sync determination based on a power mode a WTRU may beusing.

In other embodiments, in addition to, or alternatively to, the use ofpower modes for power control, power-efficient tracking may be used. Insome embodiments, a WTRU may process a re-synchronization signal (RSS)transmitted by a base station, such as a gNB, in conjunction with a DRXON duration time interval. The RSS may be used for the purpose of atleast one of AFC, time synchronization, beam management or CSImeasurement.

In some embodiments, the RSS is transmitted by the gNB and processed bythe WTRU in an identified time window. The RSS reception time window maybe linked to the DRX on-duration for a WTRU either by configuration orby application of processing rule. For example, the RSS reception timewindow may be set to start N1 OFDM symbols prior to the beginning of thefirst timeslot of a DRX on-duration window and is set to end N2 OFDMsymbols before. Alternatively, the RSS reception time window starts N1timeslots before and ends N2 timeslots before the DRX on-duration forthe device. In embodiments, N2 may be set to zero. Alternatively, theRSS reception window may be configured or applied to the first timeslotor timeslots of a DRX ON duration. It may not be necessary that the RSSoccupy the entire RSS reception time window. The RSS may be present overthe entire time interval [N1, N2], or it may start only during this timeinterval. The RSS may require less time for transmission than providedby the configured or applied RSS reception time window. Theconfiguration of the RSS reception time window for use by the WTRU maybe linked to the configured DRX parameters. The RSS reception timewindow may have a larger minimum size when DRX counters and/or timersare configured.

In other embodiments, the RSS is transmitted by the gNB and processed bythe WTRU in an identified set of frequency resources. The RSS receptionbandwidth window for use by a WTRU may be either known by configurationor by application of a processing rule in the WTRU.

For example, the RSS reception bandwidth window may be set to correspondto the currently active DL BWP for which the WTRU processes the incomingPDCCH on a DRX on-duration window. Alternatively, it may correspond toan identified subset of frequency domain resources linked to the activeDL BWP of the WTRU. Alternatively, the RSS reception bandwidth windowmay correspond to a determined subset of frequency resources, contiguousor not contiguous, and determined by configuration through RRC. Inembodiments, multiple RSS reception bandwidth windows may be configuredfor a WTRU.

When the RSS is transmitted by the gNB and processed by the WTRU in anidentified time window, such as described above, coarse frequency/timingtracking functionality in the WTRU may be implemented while incurringminimal wake-up overhead. Unlike conventional NR technology, the WTRUdoes not need to wake up and power on significant parts of its RF and BBreceiver chains for the purpose of AFC, even though the next DRXon-duration period may be many tens or hundreds of milliseconds away. Byproviding an RSS scheduled to start a couple of OFDM symbols ortimeslots just prior to or coinciding with the beginning of the DRX-onduration window, the WTRU may power on its RF and BB parts only whenneeded. Similarly, by processing the transmitted RSS in frequencyresources linked to the active DL BWP, the WTRU may avoid frequencyre-tuning in order to receive and process the SSB or SSBs that do notusually coincide with the active DL BWP. Re-tuning the WTRU receptionbandwidth costs power incurs a penalty in terms of a longer receiveron-time for BWP switching. Further, the RSS may also be employed for thepurpose of beam management.

In other embodiments, the re-synchronization signal may be process bythe WTRU in a set of identified REs in an RSS reception time andfrequency window. In embodiments, the RSS may be transmitted as one or aset of REs configured a as CSI-RS resource set. For example, the RSS maybe configured as a CSI-RS resource set. The RSS may be configured as aCSi_RS resource set where every 4th OFDM symbol over a configurabletransmission interval of one or multiple timeslots may be used withevery RSS-carrying OFDM symbol carrying 3 RSS subcarriers. Whenconfigured as a CSI-RS resource set, depending on the type of CSI-RSresources configured, zero-power or non-zero power, dynamic signaling inthe DCI may be used to rate-match PDSCH transmissions to other devicesaround the RSS resources. Similarly, existing configuration messages inuse for CSI-RS may be reused to indicate the RSS configuration.

In other embodiments, the RSS may be transmitted over a contiguousfrequency bandwidth occupying more than one RB and occupying one or moreof multiple OFDM symbols, not necessarily contiguously. For example, theRSS may be transmitted as a length 127 m-sequence occupying 12 RBs overan OFDM similar to the PSS but using a distinct m-sequence generator.These RSS carrying symbols may be repeated or a set of symbols may beused. In such embodiments, an existing implementation may largely bereused in the device to realize the RSS functionality. Further, by usingRSS in the form of CSI-RE resource sets defined at RE-level, existingR15 NR signaling may be used to rate-match the PDSCH of other devicesaround the RSS, which may avoid decoding degradations and schedulingrestrictions.

In other embodiments, the RSS sequence may be generated using anidentifier configured by the gNB or determined by the WTRU. For example,an identifier linked or identical to the C-RNTI in use by the WTRU maybe used to determine the RSS encoding sequence. This may includegeneration of RSS sequence elements or operations such as scrambling theRSS sequence with a second sequence. A reception time instant parameter,such as a symbol or timeslot number may be used to derive the RSSsequence. An explicitly singled value may be used to determine the RSSsequence. In such embodiments, interference may be randomized andreception quality of the RSS may be improved.

In some embodiments of WTRU receiver processing when operating in thepresence of a configured RSS occurrence, a WTRU may determine a DRX ONduration, determine a processing interval for reception of an RSS,configure its receiver for reception of an RSS in a set of identifiedtime and frequency resources, determine the presence or absence of RSS,determine an oscillator and/or timing correction value, and then applythe correction value and proceed to PDCCH reception. Any of these stepsmay imply several more known intermediate steps, for example channelestimation occurring while processing PDCCH candidates of a receivedCORESET.

In some embodiments, use of the RSS by the WTRU may be determined to beapplicable when a condition is met. For example, the RSS may be presentand part of WTRU receiver processing for a DRX ON duration, when a timeror counter value has expired since the last time that data or control orsuitable RS or SSB was received by the WTRU while in active time orduring DRX ON duration. The duration of the timer may be pre-defined orconfigured by higher layers. In this way, the maximum amount of time andmaximum oscillator drift incurred by a WTRU not waking up for coarse AFCmay be controlled to not exceed some acceptable value. The gNB, knowingabout the DRX ON duration or active time of a WTRU, may transmit an RSSto the WTRU if a counter or timer since last data/control receptionexceeds a given value. It may not transmit an RSS if below the givenvalue. This may minimize overhead from network perspective.

In another example, the WTRU may determine the need for or presence ofan RSS linked to the DRX ON duration based on a signal level receptionthreshold. For example, the RSS may be present and part of WTRU receiverprocessing if the WTRU-experienced DL pathloss is in excess of athreshold value, which may include an offset value. The eNb mayconfigure a signal threshold above which no RSS may be transmitted andbelow which an RSS is linked to the determined DRX ON duration.

In another example, the RSS may be present only on a condition that itis not in active time or that one or a plurality of DRX timers are notrunning, such as at least one of an inactivity timer, a UL or DLretransmission timer, and a DL or UL HARQ RTT timer. In another example,the RSS may be configured to be present only when the active BWP is oneof a subset of the configured BWPs.

FIG. 18 is a signal diagram 1800 of an example of processing an RSS inconjunction with a DRX ON duration time interval. In the exampleillustrated in FIG. 18 , a WTRU may receive an RSS 1802 in one of anidentified time window or set of frequency resources linked to the DRXON duration 1806 of a DRX cycle 1808. The RSS may be used for AFC, timesynchronization, beam management and/or CSI measurement just prior tothe start of the ON duration 1806. The WTRU may monitor PDCCH monitoringoccasions 1804 during the ON duration 1806. The WTRU may also receive anRSS 1812 during an RSS reception window 1822 just prior to the ONduration 1820 of the DRX cycle 1824. An RSS aperiodic NZP-CSI-RSresource set 1826 is also shown in detail for the RSS reception window1822. The device may be scheduled during PDCCH monitoring occasion 1814,and a timer may be started or re-started. The timer may expire (1816),and the device may stop monitoring the PDCCH occasions in response tothe timer expiry.

Although features and elements are described above in particularcombinations, one of ordinary skill in the art will appreciate that eachfeature or element can be used alone or in any combination with theother features and elements. In addition, the methods described hereinmay be implemented in a computer program, software, or firmwareincorporated in a computer-readable medium for execution by a computeror processor. Examples of computer-readable media include electronicsignals (transmitted over wired or wireless connections) andcomputer-readable storage media. Examples of computer-readable storagemedia include, but are not limited to, a read only memory (ROM), arandom access memory (RAM), a register, cache memory, semiconductormemory devices, magnetic media such as internal hard disks and removabledisks, magneto-optical media, and optical media such as CD-ROM disks,and digital versatile disks (DVDs). A processor in association withsoftware may be used to implement a radio frequency transceiver for usein a WTRU, UE, terminal, base station, RNC, or any host computer.

What is claimed is:
 1. A method, implemented in a wirelesstransmit/receive unit (WTRU), the method comprising: receiving a timedomain resource allocation (TDRA) list configuration including aplurality of entries, each of the plurality of entries comprisinginformation indicating a resource allocation that includes a slot offsetvalue; receiving layer 1 (L1) signaling that indicates a minimum slotoffset value; decoding a first downlink control information (DCI)received in a physical downlink control channel (PDCCH) transmission ina slot; obtaining, from the decoded first DCI, an index identifying oneof the plurality entries in the TDRA list; retrieving, from the TDRAlist, a particular slot offset value identified by the index; comparingthe particular slot offset value with the minimum slot offset value; andon a condition that the particular slot offset value is less than theminimum slot offset value, determining that the entry identified by theindex is invalid.
 2. The method of claim 1, further comprising: notreceiving a PDSCH transmission in the slot that is offset from the sloton which the first DCI was decoded by the particular slot offset valueon a condition that the entry identified by the index is determinedinvalid.
 3. The method of claim 1, further comprising: determining thata minimum aperiodic channel state information reference signal (CSI-RS)offset for aperiodic CSI-RS reporting is equal to the minimum slotoffset value received in the L1 signaling for a bandwidth part (BWP). 4.The method of claim 3, further comprising: decoding a second DCI andobtaining a CSI-RS reporting trigger from the decoded second DCI, theCSI-RS reporting trigger identifying a resource set that is configuredwith a particular trigger offset for the aperiodic CSI-RS reporting;comparing the particular trigger offset to the minimum aperiodic CSI-RSoffset; on a condition that the particular trigger offset is less thanthe minimum aperiodic CSI-RS offset, not reporting CSI associated withthe identified resource set in response to the CSI-RS reporting trigger.5. The method of claim 4, further comprising reporting CSI associatedwith the identified resource set in response to the CSI-RS reportingtrigger on a condition that the particular trigger offset is greaterthan or equal to the minimum aperiodic CSI-RS offset.
 6. The method ofclaim 4, wherein the WTRU is configured with a CSI-RS report triggerstate list that includes one or more entries, each of the one or moreentries comprising one or more resource sets and each of the one or moreresource sets includes identification of a set of time-frequencyresources and a trigger offset for the resource set.
 7. The method ofclaim 6, wherein the L1 signaling indicates a power mode that the WTRUis to operate in that corresponds to the minimum slot offset value. 8.The method of claim 7, wherein the power mode is a power savings mode.9. The method of claim 1, further comprising: receiving L1 signalingthat indicates a normal power mode; activating the normal power mode;and determining that all entries in the TDRA list and the CSI reporttrigger state list are valid on a condition that the normal power modeis activated.
 10. The method of claim 1, further comprising receiving aphysical downlink shared channel (PDSCH) transmission in a slot that isoffset from the slot on which the first DCI was decoded by theparticular slot offset value on a condition that the particular slotoffset value is greater than or equal to the minimum slot offset value.11. A wireless transmit/receive unit (WTRU) comprising: a transceiver;and a processor, wherein the transceiver and the processor areconfigured to receive a time domain resource allocation (TDRA) listconfiguration including a plurality of entries, each of the plurality ofentries comprising information indicating a resource allocation thatincludes a slot offset value, wherein the transceiver and the processorare further configured to receive layer 1 (L1) signaling that indicatesa minimum slot offset value, wherein the transceiver and the processorare further configured to decode a first downlink control information(DCI) received in a physical downlink control channel (PDCCH)transmission in a slot, wherein the transceiver and the processor arefurther configured to obtain, from the decoded first DCI, an indexidentifying one of the plurality entries in the TDRA list, wherein thetransceiver and the processor are further configured to retrieve, fromthe TDRA list, a particular slot offset value identified by the index,wherein the transceiver and the processor are further configured tocompare the particular slot offset value with the minimum slot offsetvalue, and wherein the transceiver and the processor are furtherconfigured to determine that the entry identified by the index isinvalid on a condition that the particular slot offset value is lessthan the minimum slot offset value.
 12. The WTRU of claim 11, whereinthe transceiver and the processor are further configured to not receivea PDSCH transmission in the slot that is offset from the slot on whichthe first DCI was decoded by the particular slot offset value on acondition that the entry identified by the index is determined invalid.13. The WTRU of claim 11, wherein the transceiver and the processor arefurther configured to determine that a minimum aperiodic channel stateinformation reference signal (CSI-RS) offset for aperiodic CSI-RSreporting is equal to the minimum slot offset value received in the L1signaling for a bandwidth part (BWP).
 14. The WTRU of claim 13, wherein:the transceiver and the processor are further configured to decode asecond DCI and obtain a CSI-RS reporting trigger from the decoded secondDCI, the CSI reporting trigger identifying a resource set that isconfigured with a particular trigger offset for the aperiodic CSI-RSreporting, the transceiver and the processor are further configured tocompare the particular trigger offset to the minimum aperiodic CSI-RSoffset, and the transceiver and the processor are further configured tonot report CSI associated with the identified resource set in responseto the CSI-RS reporting trigger on a condition that the particulartrigger offset is less than the minimum aperiodic CSI-RS offset.
 15. TheWTRU of claim 14, wherein the transceiver and the processor are furtherconfigured to report CSI associated with the identified resource set inresponse to the CSI-RS reporting trigger on a condition that theparticular trigger offset is greater than or equal to the minimumaperiodic CSI-RS offset.
 16. The WTRU of claim 14, wherein the WTRU isconfigured with a CSI-RS report trigger state list that includes one ormore entries, each of the one or more entries comprising one or moreresource sets and each of the one or more resource sets includesidentification of a set of time-frequency resources and a trigger offsetfor the resource set.
 17. The WTRU of claim 16, wherein the L1 signalingindicates a power mode that the WTRU is to operate in that correspondsto the minimum slot offset value.
 18. The WTRU of claim 17, wherein thepower mode is a power savings mode.
 19. The WTRU of claim 11, wherein:the transceiver and the processor are further configured to receive L1signaling that indicates a normal power mode, the transceiver and theprocessor are further configured to activate the normal power mode, andthe transceiver and the processor are further configured to determinethat all entries in the TDRA list and the CSI report trigger state listare valid on a condition that the normal power mode is activated. 20.The WTRU of claim 11, wherein the transceiver and the processor arefurther configured to receive a physical downlink shared channel (PDSCH)transmission in a slot that is offset from the slot on which the firstDCI was decoded by the particular slot offset value on a condition thatthe particular slot offset value is greater than or equal to the minimumslot offset value.